Ilya Melnikov - Artistic processing of metal. precious metals

2. Finishing and artistic processing of jewelry

Finishing and artistic processing of jewelry is carried out in order to increase the artistic value and wear resistance of products, the anti-corrosion resistance of their surfaces and to give the products an appropriate presentation. Finishing processes can be classified into three types: mechanical finishing - polishing, embossing, engraving; decorative and protective coatings - enameling and blackening; chemical processing - oxidation and galvanization.

Polishing

The essence of the polishing process is to remove microroughnesses from the metal surface, which achieves a high class of cleanliness and surface specularity. Polishing is one of the finishing processes for processing products. Jewelry can be polished before being oxidized - coated with a layer of another metal. If the products cannot be polished as a whole after assembly, some parts are polished during assembly. Two types of jewelry polishing are mainly used: mechanical and electrochemical. Mechanical polishing is called piece-by-piece polishing of products with and without abrasive. Mass methods of polishing - in drums and containers, despite the fact that they are actually also mechanical, are called tumbling and vibration processing.

Electrochemical polishing is the anodic etching of products in an electrolyte environment under the action of an electric current, i.e., the reverse process of gilding and silvering.

mechanical polishing. Mechanical abrasive polishing is carried out on polishing machines using elastic wheels and brushes with abrasive pastes, and non-abrasive polishing is carried out manually with special polishing. For abrasive polishing of jewelry, two-spindle machines are used, equipped with nozzles for attaching a polishing tool and exhaust devices with waste collectors for the subsequent extraction of precious metals.

Tools for mechanical polishing are elastic circles, brushes and polishers (Fig. 124). They must hold abrasive pastes well on the surface and be resistant in operation. The purpose of a polishing tool depends on the material from which it is made and its shape.

Felt circles (feelers) - used for the initial polishing of smooth, even and convex surfaces. This is a high quality polishing tool, very durable in use, its hardness depends on the roughness of the material. The size of the circles is determined by their outer diameter. The felt wheel, thanks to the hole in the center, is screwed onto the conical screw nozzle of the polishing machine spindle.

Hair circles (disk brushes) are used for polishing jewelry of complex design with an openwork and embossed surface. The disk brush has a wooden base - a supporting wooden disk, on which protruding hair brushes are fixed around the entire circumference. The elasticity of the brush is determined by the stiffness and length of the hair. You can increase the stiffness of the brush by shortening the length of the hairline. Hair circles are attached to the polishing machine in the same way as felt circles.

Cloth circles are used for final polishing (brilliance). They are disks made of material, assembled in packages. As a material can be used: coarse calico, calico, linen, flannel. The disks collected in a package are fixed between wooden cheeks with an axial hole. When assembling the package, it is advisable to use several spacers from discs of smaller diameter, this improves the ventilation of the circle and increases its service life.

Thread circles (fluff) - are used, as well as cloth ones, to bring gloss to the surface of the product. By design, they resemble hair, the difference is that instead of a hairline, they have a filament cover. Thread circles are very soft.

All listed circles are used as a machine tool. Polishing (abrasive) pastes are applied to the surface of each rotating wheel. The grit size of the paste is selected depending on the stage of polishing products (initial or final). Polishing pastes contain fine abrasive powders, live bonds and special additives. The abrasive material is chromium oxide, crocus (iron oxide), silicon oxide. The following are used as binders in pastes: stearin, paraffin, technical lard, caeserin, wax, oxidized petrolatum. Special additives are: bicarbonate of soda and oleic acid, which are introduced to activate the polishing process, turpentine and kerosene - to change the viscosity. Chromium oxide-based pastes are green, while those based on iron oxide are red.

These pastes are available in the solid state. They are applied to the polishing wheels during the rotation of the circle by lightly touching the surface of the circle with a paste. When polishing products made of precious metals, GOI pastes are used for primary and basic surface treatment, and crocus pastes are used for final finishing. The composition of the pastes is selected depending on the hardness of the alloys to be polished.

Polishers are hand tools for mechanical polishing. The essence of polishing is to smooth the surface of the product with a smooth section of the polisher. The smoothing of the surface occurs without the use of abrasive pastes. Polishers are used to process hard-to-reach places, small areas among a matte or engraved surface, and electroplated coatings.

Polishers are steel and hematite. A steel polisher is made from good tool steel (needle files are often used) in the form of a rod with a polished end (working part). Most often, the working part of the polisher has an oval shape, but polishers with a working part of various shapes are also used to treat surfaces of any nature.

Hematite polishers are similar in shape and length to paint brushes. At the end of the wooden rod, a smoothly processed hematite (bloodstone) is fixed, which is the working part of the polisher. The working part of hematite polishers, as well as steel ones, is more often rounded, but other forms of stones are also used. A mandatory requirement for polishers, regardless of their shape, is a smoothly polished surface of the working part.

Mechanical polishing is the highest quality and the only final type of polishing (after hydraulic and electrolytic polishing, products become glossy mechanically), but it has a significant drawback - each product is polished individually. In this regard, mass types of polishing - tumbling and vibration processing - have become more widespread in the jewelry industry.

Tumbling is a method of mass polishing products in a rotating drum in an environment of polishing and detergents.

The polishing agent loaded into the drum along with the products are steel balls with a diameter of 1 to 3 mm (depending on the product). At the same time, a washing solution is poured into the drum.

Its composition is as follows (g/l): Ammonia 25%..... 15 Soap shavings..... 15 Detergent..... 10 Bleach...... 8 Sodium bicarbonate... 7 Sodium chloride ..... 2 other solutions are used that speed up the process, for example, solutions of 72% soap, caustic soda, soda ash, slaked lime, sodium nitrate, etc. The drum itself can be cylindrical, smooth and faceted (6.8 faces). The casing is metal, lined with rubber from the inside. Rubber protects products from nicks and seals the drum. Recently, rubber drums have been used.

The essence of the process lies in the fact that when the drum rotates, the product and metal balls (filler) are in constant motion, and as a result of mutual friction, the surfaces of the softer metal (products) are smoothed. The detergent composition, which is also in motion, washes away dirt and speeds up the polishing process. The optimal drum rotation mode for gold and silver items is 70--80 rpm. The drum is loaded halfway, and the balls (by volume) should be twice as many as the products. The duration of tumbling is from 2 to 8 hours, depending on the condition of the surface. At the end of the tumbling, the products are separated from the balls, washed, and then polished on polishing machines.

Vibroprocessing. Vibration processing of products is a polishing process similar to tumbling in a filler medium, but not in a rotating drum, but in a vibrating container. The essence of the process is the same - the surface of the products is smoothed as a result of mutual friction. But the time of polishing products during vibration treatment is much shorter than during tumbling - 60--80 minutes. The polishing process takes place in a closed container of the vibrating machine, where the filler and cleaning solution are placed along with the products. As a filler, which occupies /z of the volume of the container, steel and glass balls are used in a ratio of 2:1. The sizes of steel balls are 2 - 6 mm, glass - 4 mm. The detergent is a solution of the same composition as in tumbling, plus wood flour - 10 g / l.

Loading into the container is carried out as follows. First, steel and glass balls are loaded, then, after turning on the vibrator, chemical components and water. Products are loaded only after thorough mixing of the filler with the detergent composition. This sequence is explained by the fact that the density of precious metals (products) is higher than the density of the filler, and as a result of vibration, the filler will be gradually forced upward, and the products will sink to the bottom of the container. At the end of the vibroprocessing process, the products are separated from the filler, washed, dried and glossy.

Both methods - tumbling and vibration processing - have a significant drawback - it is impossible to polish products of complex configuration with sharp edges and sharp transitions. electrochemical polishing. This is an anodic etching process, as a result of which microroughnesses present on the surface are dissolved and the surface is smoothed. Compared with other types, electrochemical polishing has a number of advantages: the ability to process places inaccessible to other methods; uniform smoothing of the metal over the entire surface, preserving the configuration of the products; reduction of losses of precious metals. Electrochemical polishing takes place in electrolyte baths subject to a certain regime.

The composition of the electrolyte for gold is as follows (g/l): Potassium cyanide KCN .... 10 Potassium iron-cyanide K4Fe6........ 20 Potassium hydroxide KOH. 0.3 Disubstituted sodium phosphate NaHPO.t- 12H20. . 60 The product serves as an anode with a stainless steel cathode, the distance between the electrodes is 10 cm. The voltage on the bath is 2.8–3 V. The duration of polishing is 5–10 minutes at an electrolyte temperature of 50–60°C. The following electrolyte is used for polishing silver (g/l): Silver cyanide AgCN ... 35 Potassium cyanide KCN . 20 Anode current density 3--5 A/dm2, electrolyte temperature 18--25°С, polishing duration 2-5 min. Another electrolyte for silver has the composition (g/l): Potassium cyanide KCN . 25 Sodium hyposulfate Na2S203 * 2H20 ...... 1 - 3

Polishing occurs at an anode current density of 2–10 A/dm2, an electrolyte operating temperature of 20–25°C, and a process duration of 5–15 minutes.

If polishing is the final process for products, then after washing and drying, the products are mechanically glossed with an abrasive paste. The final rinse after polishing completes the jewelry finishing process.

For washing jewelry, modern enterprises are equipped with an ultrasonic unit, the tank of which is filled with a washing solution of the following composition (g/l): Aqueous ammonia solution 25% ........ 40 Laundry soap 70%. 0.5 Cleaning cycle time up to 3 min, solution temperature 60°C.

Chasing is a type of artistic processing of metals with special punches - embossing, as a result of which the workpiece takes on a relief image. The essence of the chasing process lies in the fact that as a result of the pressure exerted on the chasing (by hammer blow), a trace remains on the metal according to the shape of the working part of the chasing. By repeated blows of various coinage, a given pattern is knocked out. Distinguish between hand and machine chasing. Chasing is considered manual if the process of punching the image is done manually. Machine chasing is a stamping operation performed on presses using dies. Modern equipment makes it possible to obtain high quality images, so stamping has greatly reduced the use of hand chasing in the manufacture of jewelry. And chasing should be considered not as a type of decoration, but as an independent type of manufacturing products, which occupies a large place in the art industry.

As materials for chasing, sheet metal with plasticity is used. These are gold, silver, copper and its alloys (tompac, cupronickel), aluminum. More often than others, copper and tompak are used, which have excellent decorative qualities, the ability to take on chemical and electrochemical coloring, acquiring high anti-corrosion properties. The plasticity of these materials allows deep drawing of the relief. The thickness of the workpiece is determined by the dimensions of the chased product. For products of small sizes, sheets with a thickness of 0.3-0.8 mm are used. The main tools for chasing are chasing and hammers.

Chasing is a steel rod, usually faceted, 90-120 lm long for small forms. The cross section of the coin should be variable. A thickening is left in its middle part for stability and vibration damping during impact. The working end of the coinage is hardened. Its other end, which serves to strike, is also slightly heated up, however, not allowing it to riveted, which saves the length of the coinage. Only the middle part remains unhardened at all - this dampens vibration. The chasings are made from steel rods of grades U7 and U8, then they are processed (on an emery sharpener or manually) so that the longitudinal axis of the chasing passes strictly through the center, this ensures the stability of the chasing during impact. When processing the coinage, its faces are preserved, most often four. The strikers differ in the shape of the working part (beat), which depends on the purpose of the tool. There are many varieties of coinage, but in addition, each coiner also uses sets of coinage of the same variety, which differ from each other in size and chisel pattern, curvature of the bulge, surface condition, etc. The main types of coinage have their own names. Below are their brief characteristics. Kanfarniki - a form of combat in the form of a blunt needle, leave a dotted mark. They are used to transfer a pattern to metal by embossing the image along the contour, as well as to finish the background with dots (shotting). The smaller the size of the product, the sharper the strike of the coinage is chosen. Consumables are a linear form of combat, resembling a screwdriver blade. Necessary for embossing a solid line. With curved lines, chisels with a curved chime are used. Consumables outline the image on the metal at the points of the kanfarnik. The length and curvature of the fight is chosen depending on the size of the pattern. Horsemen - have a flat fight of various forms. They are used to align planes, raise or lower flat areas of the image. The difference in the forms of battle is due to the nature of the pattern, in particular, the contour line of the flat area. The surface treatment of these embossments is also different. To obtain a brilliant trace, polished burners are used, for a matte trace, polishers with varying degrees of roughness of the battle are used. Purushniki - the shape of the fight is round with a bulge, the size and bulge of which are different. Puroshniki provide a deep drawing of the relief and obtaining a pitted texture.

Boboshniki - the shape of the battle is convex oval. They serve, like fur coaters, for relief drawing. Tubes - the shape of the battle is round concave, spherical recesses of different sizes. Unlike puroshniki with a pitted trace, the tubules leave a convex trace, deepening the contour of the bulge.

Textured - coinage, on the battle plane of which a notch is applied. The notch can be striped, checkered, dashed, etc. They are used to finish a stamped image or background.

Special - stampings that have a pattern or a fragment of a pattern on the surface of the battle for repeated repetition on the product. It can be a leaf, a flower, an element of an ornament, a rope, a cord, etc. The hammers used for chasing have a round or square striker, the surface of the striker is flat. The toe of the hammer (the opposite part of the striker) is made spherical, of various diameters. The spherical part of the hammer serves to lift the relief without the use of a chisel. The shape of the hammer handle is also unusual - it is bent down towards the striker and thickened, this allows you to strike a certain force for a long time.

Soft metals or specially welded resins are used as devices for chasing, playing the role of lining matrices. From metallic materials, lead or an alloy of lead with tin in a ratio of 1:1 can serve as a matrix. Metal matrices, which allow you to get a clearer image, are used for small jobs or when processing a separate area of ​​the image. The dimensions and shapes of the matrix may be different, but its thickness must be at least 10 mm.

From metal materials, the matrix can be a resin mixture, elastic and sticky. It is convenient in that the sheet blank is firmly fixed on its surface. The composition of the resin mixture includes: artificial or natural resins, finely sifted dry earth (can be replaced with a mixture), wax and rosin. The earth acts as a filler, its content regulates the hardness of the mixture. The viscosity of the mixture is achieved by the presence of wax, and the stickiness and strength are achieved by introducing rosin into the composition of the mixture. The mixture is prepared on fire with constant thorough stirring. Then it is poured into shallow wooden boxes, the dimensions of which are slightly larger than the dimensions of the hammered blank. When chasing small forms, a cast-iron ball (shrabkugel) is used, which has a cut with small sides, where resin is poured. A screw shrabkugel is also used, a metal bar coated with a resin layer is clamped into its connector. A tracing paper taken from a drawing (photographs, postcards, etc.) serves as a working template for a chaser. The dimensions of the sheet blank are determined by the template, so that the blank has free margins relative to the template. To firmly secure the workpiece, its edges are bent down. The flanging of the edges (bending) can be done with pliers, a hammer on a dressing plate or on special small hand rolls with a roll bending profile. Many chasers simply fold the corners down to provide a grip. For better adhesion of the surface of the workpiece with the resin, the workpiece must be well annealed and bleached or lightly etched. The surface of the resin is evenly heated with a soldering iron until the top layer is completely softened, and the workpiece is also heated at the same time. The hot billet (hold it with pliers) is lowered obliquely onto the softened surface of the resin so that air does not linger under the plate. Having drowned the curved edges of the workpiece, it is once again heated from above so that the resin fits snugly, without bubbles, to the workpiece. In places where air bubbles form, the metal bends, and sometimes breaks through. In the process of pitching, it is necessary to ensure that the resin does not ignite, otherwise it will lose its adhesive and plastic properties. After the resin has cooled, the workpiece is ready for use.

The drawing is applied from the template directly to the metal or glued to the workpiece using a soapy solution or glue. Then the contours of the image are minted with a goblet, leaving a clear dotted mark. The contours scanned on the metal are minted with a consumable, turning the dotted line into a solid one. The sharpness of the strike of the coinage is chosen in accordance with the size of the product. The background is lowered and leveled with polishers, starting with a contour line minted with a consumable. The background is lowered to the depth of the contour line (expenditure) and as a result a clear relief image with the background is revealed. Stretching under the action of chisels, the metal is hardened and annealing is required, especially in the places of contour steps. The heated workpiece is removed from the resin and, evenly heated by the apparatus, is annealed. At the same time, the adhering resin residues burn out, forming soot, which is removed with a metal brush (krautsbyur) made of thin copper wire in the form of a brush. After annealing, in order to punch out the front relief, the workpiece is again ground with the face down in order to mint the front relief on the reverse side. If there should not be a clear pattern on the product, then the plate is placed on a lead, wooden, rubber or felt base (face down) and the wrong side is minted with appropriate embossing in places where the front relief is raised. This operation causes distortion of the workpiece, which is eliminated by editing the background on a flat dressing plate.

For final processing, the annealed workpiece is again ground, but this time the relief cavities obtained on the sheet are pre-filled with resin. Depending on the accuracy and complexity of the image, the product can be painted up to 4-5 times. The final refinement of the relief and background is carried out with greater care. The coinage for this is chosen not only in shape, but also on the surface of the battlefield in order to give the surface of the product a certain texture. The product removed from the resin is annealed, cleaned of carbon deposits and bleached, then cut to the final size. Further processing is carried out according to its purpose. If the product does not require soldering, it is brushed, oxidized, polished.

Engraving

Engraving is a type of artistic processing of a product, which consists in cutting a pattern on a product with chisels. In jewelry practice, manual two-dimensional (planar) engraving is used, in a different way - engraving for the sake of appearance. Manual engraving is a complex and time-consuming process that requires great skill, endurance and concentration from the performer. Jewelry engraving is done at a jewelry workbench using engraving fixtures and tools.

View engraving is a common type of hand engraving. It includes the execution on products of drawings and dedication inscriptions under gloss and under blackening.

When engraving, the product must be strengthened. For this purpose, use: wooden vices, mounting plates, shrabkugel and fenders.

Wooden vise - manual and desktop with different shapes of jaws, the same as for setting stones. They are used to strengthen bulk products. Mounting boards - made from viscous wood. Serve to strengthen flat products. The horizontal dimensions of the boards depend on the dimensions of the product, their thickness is 20-25 mm. You can strengthen the product on the boards with the help of carnations, pressing the plate along the contour with caps, sealing wax and setting pastes. Shrabkugel (ball vise) - is a cast-iron ball about 130 mm in diameter, in which a segment is cut off on top and a groove is cut in which a plate with the product is clamped with bolts. In order for the product to be freely moved at any angle, a leather ring is placed under the shrabkugel. Kranz (engraving pillow) - a heavy leather or canvas round pillow, tightly stuffed with sand. Fender diameter 180-200 mm. It serves as a lining for a mounting plate or desktop wooden vise for free maneuvering of the product. Kranz is the simplest and most common engraving device. It is usually made by the craftsmen themselves. To do this, two circles with a diameter of 180-200 mm are cut out of thick leather (3-4 mm), soaked in water and sewn wet around the circumference at a distance of 5 mm from the edge. The circle is not completely stitched - 30-50 mm are left unsewn. Fine, dry, washed sand is poured into the resulting bag through an open hole. Then the hole is sewn up and the pillow is leveled on the table.

Shtikheli. As already mentioned, the product is engraved with engravers. A chisel is a steel chisel, like a bar-tack, inserted into a mushroom-shaped wooden handle. Cutter length 100--120 mm. Stichel are made from U12A or KhVG tool steels. In addition to these steels, you can use: silver bar steel, spring strips, outer rings of ball bearings (straightening them), small flat files and straight razor blades. A mandatory requirement for a chisel is a good seal and proper sharpening. The quality of the work performed largely depends on this. If the engraver is not local, it quickly becomes dull or its cutting edge is crushed, but if it is overheated, its cutting edge constantly crumbles. Heat-treated chisels are inserted into handles of various lengths to fit the chisel to the hand as it is ground down. Handles are made from 30 to 70 mm long. The neck of the handle is strengthened with metal rings, which protect it from cracking during the nozzle. The tail of the blade enters the pre-drilled handle for 2/3 of its length. The lower part of the fungus of the handle (on the side of the blade) is chipped, which makes the engraver the most convenient for work - it allows you to tightly clasp the handle with your little finger, holding it, and set any angle between the blade and the product during engraving.

Finishing of external and internal cylindrical surfaces

Production of precast concrete structures

It is clear to everyone how important the surface finish of reinforced concrete structures and parts is. After the general impression of the structure, a closer acquaintance with it occurs, and then the first impression is either confirmed or changed ....

It includes the following processes: melting, rolling, wire drawing, cold stamping, punching, drawing, bending, embossing, filigree (scanning), assembly and soldering of products, decorative and protective finishing, grinding, brushing ...

Jewelry manufacturing

In professional language, enameling is the application of fusible glass to the surface of a metal (more on the technology of hot and cold enamels). Jewelry made on a metal base is also covered with colored enamels...

Casting Gold, silver, bronze have high fusibility and are easily poured into molds. Castings follow the model well. Casting is one of the most ancient methods of metal processing. Archaeological excavations in Egypt and Babylon confirm...

Propaedeutics in the technology of artistic processing of materials

Trihedral-notched carving - the most ancient type of geometric carving - was the most common, which is quite understandable: after all, the only tool with which it was performed, an ordinary knife, was always at hand ...

Propaedeutics in the technology of artistic processing of materials

Today, everyone wants to make their home not just beautiful, but memorable and unique. For this, decorative glasses are used. They give the interior a unique style ...

Propaedeutics in the technology of artistic processing of materials

Embossing There are several types of embossing. In industrial production, various stamping methods are used, when the pattern on the skin is squeezed out using molds. In the manufacture of art products, stamping is also used ...

Jewelry

Production is one of the most important factors influencing the formation of consumer properties and the quality of jewelry. One of the features of the production of jewelry is that ...

Indeed, where is the only one among the many professions that is worth devoting your whole life to and which corresponds to your personal characteristics and inclinations? Will you be able to take the necessary place in life, so as not to experience bitter disappointment later. Probably, there are no people who would not care about these issues. Difficult for a person of any age, for you, young readers, they are especially difficult. And despite this, they must be solved at your age, since the goal chosen in youth becomes the meaning of all life. Of course, it is very difficult to choose a profession. A fairy-tale knight at a crossroads needs to choose one of three roads, but you need one of forty thousand, according to statistics.

You can, for example, become a physicist, research chemist, test pilot, but you can also become a worker. Whatever a person wants to become, the most important thing for him should be the right attitude to the matter; it must be active, purposeful. In any profession, there is always something to think about, what to look for and try. The main thing is to find your favorite thing!

Of course, there are those among us who have long thought about the question of their future, those who have a firm goal in life and are moving towards this goal. This book will help those who have not yet made a choice, who have not defined their vocation.

Take any household item, large or small, be it wood, clay or metal, you will certainly notice that the hand of the artist has touched it; he took care that the object was not only convenient, but also attractive in shape, color and surface character. The purpose of our book is to tell readers, especially young people, about folk art, artistic crafts, about people who have connected their lives with their favorite business. Alexander Stepanovich Green said that these people are romantics who comprehended a simple truth in order to do the so-called miracles with their own hands.

I had a chance to visit one of the enterprises of folk crafts, where they have been engaged in pottery for a long time. There was a potter's wheel in the workshop - the most ancient machine on earth. Everywhere - on the floor, shelves - finished elegant products: ceramic vases, jugs, kumantsy, bochata. The master takes a lump of clay moistened with water and begins to rotate the circle. The precise movements of his dexterous hands worked wonders before my very eyes. With seeming ease, plastic outlines of the future vessel began to appear from a piece of shapeless mass. A piece of clay began to acquire a new state, receiving the form conceived by the master. It took only three minutes to make a jug. But the miracles continued! On the dried clay with a brush, the master began to apply bright unprecedented flowers and unusual, fantastic birds with huge eyes. After being in the potter's kiln, the paints on the painted jug flared up either with intensely bright or delicate shades.

Are these not the miracles that A. S. Green spoke about, miracles made by one's own hands. What exquisite taste and impeccable craftsmanship must be possessed in order to carry out this extraordinary transformation on the simplest machine tool from simple material.

Folk art in its development was closely connected with everyday things that accompanied a person throughout his life. From simple materials, simple tools, by hand, the master himself made each item from beginning to end. They created things similar to each other, but always marked by a unique originality. The folk master knew how to adapt to the characteristics of the material and subordinate it to his tasks.

Any motif of an ornament on an object, be it geometric or floral, is located not by chance, but in strict accordance with how the object itself is built. Works of folk art are remarkable primarily for their expediency. They give a visual representation of the fact that the people who created them and used them felt the measure of beauty in everything. Concern about the expediency of the forms of a household item did not exclude the need for their decoration, which gives color and elegance to all folk art, from the hut to small household items.

Folk art has developed as a result of the work of many generations; the experience of processing the material, passing from teacher to student, led to perfection. Entire families, villages, villages mastered the skill. Thus, folk art crafts were born. Here the skill of each individual performer is a particle of the creative work of the whole team. But the people have always noted especially skillful and skilled, their highly artistic samples served as a standard, which was followed by the rest. There were legends about them from generation to generation.

Depending on local conditions and the availability of material, each folk art craft had and still has its favorite themes, ornaments, color schemes, features of the shape of products, and its own production specifics.

The world of objects around us is complex and diverse, every day, hourly, more and more new forms appear, new materials are used, fashions change. And how, against this background, objects of folk art are remarkable for their original beauty! They are valuable because they are made by hand, they never exactly repeat one another. With their shape, originality of the pattern, bright, rich colors, they accentuate and complement the decor of our apartments, introducing a special, unique flavor into them.

The richest heritage of folk art is being used more and more widely; It has become commonplace when a professional artist works in collaboration with a craftsman at art craft enterprises, and architects increasingly involve folk craftsmen in the design of the structures they create. The demand for handicrafts has also expanded; it is no longer limited to the borders of our republics. The need for them is huge not only in our country, but also abroad.

The functions of products made in art crafts have been enriched; utilitarian in traditional life, these items become souvenirs and decorative items. Works of art crafts easily fit into the atmosphere of a modern interior, as the folk art of today, as well as professional art, reflects today's tastes and aesthetic needs. Having become acquainted with the features of folk art and the formation of art crafts, we will touch on the history of the creation and development of folk crafts associated with metal processing. Knowledge of the historical past will help you better understand the origins of this area of ​​art, explain how certain traditions, artistic techniques, plots and themes appeared in it.

01. Image of a deer. Gold. Black Sea region. 6th century BC e.

The artistic processing of metal has an exceptional place in the history of decorative art. Craftsmen, using various metals, enamels, gems, using many processing methods, managed to create works of perfect beauty. Metal has amazing properties. It can be melted, cast, stamped, drawn, twisted, engraved, blackened, enameled and given various shades. Therefore, metal has long attracted people with its capabilities. National features of artistic creativity in the field of metal processing appeared long before the formation of the Russian state. For the study of Russian art, the work of those peoples who lived next to our ancestors, with whom there was an exchange of material and spiritual values, is of great importance.

In the first millennium BC, vast territories from the foothills of Altai to the shores of the Black Sea were inhabited by a people that the ancient Greeks called the Scythians. During the excavations of Greek colonies and Scythian mounds, art treasures and one of the most precious treasures - "Scythian gold" were found. Remarkable works of jewelry art were found among them: golden earrings (pendants), a golden comb, chased vessels, richly decorated golden sheaths of swords, luxurious jewelry of Scythian kings and noble people of that time, and other precious things.

Highly artistic works created in the ancient period speak of an extraordinary rise in decorative art, a high level of artistic skill and a variety of methods used to process and decorate precious metals.

The tribes that inhabited our lands - the Sarmatians and then the Antes and Slavs - before the formation of their state in their art, borrowed a lot from the Scythians, but created a bright original art. Numerous excavations on the territory of the USSR, in the Kul-Oba burial mounds, near Kirovograd, in Kelermes in the Kuban, in the village of Martynovka south of Kiev, in Staraya Ladoga and other places where samples of works of decorative art made of metal were found, reveal to us the prehistory of ancient Russian art .

In the 10th - 12th centuries, artistic metal processing received a comprehensive and widespread development not only in cities, but also in villages. Everywhere blacksmiths were the first jewelers who forged and cast various pieces of jewelry. In blacksmithing, cold and hot forging and casting were used. The weapons were decorated with silver and gold inlays. They made jewelry, pendants for necklaces and clothes from copper. From sheet metal, embossing and embossing was used for many products.

02. Tury horn. Silver. Chasing, black. Ornament detail. 10th century

The successes of Kyiv enamel masters were especially great. Enamel was used to decorate a wide variety of items made of gold, silver, bronze and copper, most often enamel was used in combination with filigree, chasing and engraving. However, enamel was sometimes a completely independent type of decoration.

03. Items of the Staroryazan treasure. XII - XIII centuries

Russian enamel of this time is known in two of its types - champlevé and cloisonne, one-color and multi-color. The most difficult in execution is the cloisonne multi-colored enamel. Thin golden partitions according to the intended pattern were soldered to a gold plate, and the gaps were filled with colored enamel.

The colorful enamel that filled certain areas of the surface of such metal items as earrings, pendants, tiaras, necklaces, buckles, significantly enlivened the latter and gave the ornament more expressiveness. Magnificently executed luxurious diadems are found in Kiev and Ryazan; they delight with their excellent technique and purity of enamel tones and are rightfully considered the pinnacle of jewelry art.

04. Zhikovnitsa (durny loop) iron

05. Berdysh. A product of Moscow artisans. XVI - XVII centuries

Kyiv niello masters showed no less skill and subtlety of artistic taste. For a long time, the background of images was filled with niello, on which light outline drawings made with a chisel stood out clearly. Somewhat later, black images appear on a light gold or silver background. The niello technique was used to decorate various jewelry items. Niello was also used in combination with other types of artistic decoration. So, in Chernigov in the mound "Black Grave" were found two tury horns, set in silver. Local craftsmen, along with niello, used contour embossing on thin sheet silver and a gilded background worked with small relief balls.

In Kievan Rus, metal products with filigree (scani) and granulation decorations were common. Decorative openwork details were made of gold, silver or copper wire, the smallest grains, rings, and by means of soldering they were connected to each other and to the base of the product. High skill and knowledge of technology allowed craftsmen to connect delicate and complex patterns of details and individual parts of objects with almost invisible solder. The art of Kievan Rus marks the brilliant flowering of Russian artistic creativity.

The Tatar yoke brought a terrible and prolonged ruin to the main cultural centers of the country. However, the artistic activity of many cities was not completely disrupted. In cities such as Novgorod, Pskov, Smolensk, Galich, cultural monuments of past centuries have been preserved and the remarkable traditions of ancient Russian jewelry art continued to develop.

In the XIV - XV centuries, the revival of many types of artistic metal processing began. One of the first to revive the art of filigree; it did not require sophisticated equipment and therefore became widespread in many Russian cities. Along with purely filigree items, there are objects where the filigree pattern is sometimes colored with mastic painted in different colors. Decorative art is especially developed in Moscow: art workshops are organized here, in which, in addition to jewelry with filigree ornaments, ceremonial weapons, dishes, goblets, and church utensils are made. For the production of items from precious metals, the best Russian craftsmen are attracted and artists and artisans from other countries are invited. The most outstanding Russian masters of the middle of the 15th century were two remarkable scanners - Ivan Fomin and monk Ambrose.

06. Tsar Cannon, Master Andrey Chokhov. 16th century

In the 16th century, jewelry again began to occupy one of the leading places. The new upsurge in the development of artistic creativity and craftsmanship was not accidental; XV - XVI centuries - this is the time for further unification and strengthening of Russian lands. As the power of the Russian state grew and international relations expanded, the need for works of applied art grew.

To create highly artistic samples, masters of jewelry were needed. Established at the beginning of the 16th century at the Moscow Kremlin, the Armory Chamber expanded significantly in the middle of the century. In addition to the armory, independent workshops are opened - chambers, including the Blacksmith's, Gold and Silver, where many skilled craftsmen worked.

Moscow becomes the largest center of artistic processing of precious metals In the workshops of the Moscow Kremlin, gold and silver craftsmen created a variety of products intended both for the royal and patriarchal courts, and for sale.

At this time, chasing and embossing were widely used. Chased works are distinguished by restrained simplicity of forms and expressive processing of every detail. Plant patterns - curly stems, herbs, graceful leaves and flowers form a calm and smooth rhythmic structure, giving balance and decorative integrity to the whole ornamental composition.

In chasing and embossing, in addition to rich floral ornaments, there are images of human figures, entire scenes, and multi-figured compositions. A feature of these images is the softness and generalization of forms, the lack of fine detailing.

Particularly subtle are products with deep-colored niello. On gold objects (cups, dishes, goblets, glasses) decorated with niello drawings, a thin black graphic pattern is very beautifully combined with a gold surface of the background; they are remarkable examples of 16th-century graphics. Russian master enamellers are mastering new methods of making enamel on filigree and embossed relief, and are successfully using it to decorate items.

The 16th century is the heyday of the Moscow gold and silver business. Without losing the beautiful ancient traditions of artistic craftsmanship, Moscow master jewelers achieve high perfection in the techniques of processing and decorating precious items.

In the 17th century, in addition to Moscow, such cities as Yaroslavl, Kostroma, Nizhny Novgorod, Veliky Ustyug, Solvychegodsk became significant centers of artistic culture. Each of these local centers had its own characteristics and traditions.

At the end of the 16th and the beginning of the 17th centuries, the nature of decorations gradually changed, they acquired greater splendor and complexity. The desire for splendor is manifested in a large number of pearls and precious stones, gold and silver items. Enamels acquire a brighter color and contrast. All this corresponds to the decorative decoration of the palace premises, where brightness, multicolor, cheerfulness began to occupy the main place.

Significant development receive engraving and niello. The collection of the State Historical Museum contains works by Russian silversmiths with complex plot drawings made using the engraving technique. New decorative techniques appeared in the nature of niello drawings. Instead of thin and clean graphic lines, conditional planar figures, large carved flowers, fruits, herbs, birds, and animals appear on a golden background of objects. They are underlined with an engraved line and processed with the smallest velvety strokes. Along with the technique of setting enamel on chased and engraved metal, items with scanned colored enamel were created in Moscow at that time.

07. Patiras. Pskov. 17th century

08. Bucket of Tsar Mikhail Fedorovich. 17th century

In addition to Moscow, the enamel products of the craftsmen who worked in Solvychegodsk are also famous. As far back as the 16th century, the production of items with painted enamels was organized here, including silver dishes, the main decoration of which was decorative painting on enamel. In the 17th century, in Solvychegodsk, simple-shaped bowls, feet, dishes were made and decorated with yellow-orange, red, green and blue flower motifs against a light background. On the products of the Solvychegoda craftsmen, one can also find portraits and plot images borrowed from drawings of books and engravings of that time.

The development of a new artistic direction in the work of Russian enamellers culminated in the appearance of enamel miniatures at the turn of the 17th and 18th centuries, which soon became the most popular variety of this art.

At the end of the 17th and beginning of the 18th centuries, there was a rapid development of the metallurgical and metalworking industries. Masters of artistic metal processing are grouped at large factories in the Urals - in Nizhny Tagil, Kushva, Kasli, Kus and at other iron foundries, where they produce artistic castings. At this time, the main traditional crafts of artistic metal processing were formed on the territory of Russia. During this period, the now operating factories "Northern Niello", the Krasnoselskaya jewelry factory, a branch of the Bronnitskaya jewelry and art factory in the village of Sinkovo ​​near Moscow were founded. It is impossible not to name such enterprises as the art factory "Yuvelir", the Volga jewelry factory "Krasnaya Presnya", the Kazakov factory of art products, "Rostov Finift", where creative teams of masters and stylistic traditions developed after the Great October Socialist Revolution.

09. Badge of gunners. 17th century

Folk art crafts are a special branch of the modern art industry, producing household and souvenir items. Craft enterprises unite craftsmen and artists of folk decorative art. At these enterprises, along with the use of various auxiliary devices and small-scale mechanization, highly skilled manual labor is used.

10. I. S. Gorelikov. Steelworker and schoolboy. Cast iron. Kasli. NIIHP. 1956

In modern crafts associated with the artistic processing of metal, traditional forms and techniques related to the distant past of folk culture, which are distinguished by a bright national identity, are carefully preserved and improved.

In the first years of Soviet power, metalworking art crafts remained small, scattered handicraft enterprises. Later, the scale of production changes, some of the enterprises become large production associations with a large number of highly qualified craftsmen and artists. In large trades, there are professional technical art schools. Here they instill love for the working profession, traditions, young masters receive an art education, learn professional techniques, and acquire various knowledge.

To improve the level of professional knowledge, to provide creative assistance in the creation of new models of products, young masters of some crafts created experimental creative groups and groups of individual apprenticeship. Many wonderful artists and craftsmen have prepared professional art schools of handicrafts.

The work of a folk master is highly valued in socialist society. Only in the Russian Federation, thirty-five crafts artists were awarded the title of laureates of the Republican State Prize named after I. E. Repin. And how many craftsmen in all the union and autonomous republics have been awarded the honorary titles of people's artist, honored master of folk art; several craftsmen were awarded the title of Hero of Socialist Labor.

In 1930, the Scientific Research Institute of the Art Industry was established, which in many ways helps the creative activity of crafts. In the laboratory of artistic processing of metal, stone and bone, a lot of experimental work is being carried out, which gives good results. Researchers together with the artists of the institute, based on traditional forms and techniques of a particular craft, create new samples of products, helping to preserve the original foundations of the art of craft.

Various methods of artistic processing of metals also have a long history. Some of them originated in ancient times, but have not lost their value to this day, others were developed relatively recently. The arsenal of a modern jeweler includes art casting, carving, engraving, filigree, embossing, notching, and various types of enamels. These techniques are still based on manual processing techniques, and therefore very time consuming. Most often they are used for author's works. Moreover, manual, exclusive production today is fundamental for creating new models of products, and for fresh style ideas.

• Enamel(from the French. "to melt"). The ancient Russian name for enamel "finift" comes from the Greek "fingitos" - "brilliant stone". Enamel is a thin layer of a glass alloy, the color of which depends on the oxides of its constituent metals. Iron oxide, for example, gives enamel a yellow or brown tint; manganese oxide - purple, brown, black; cobalt oxide-oxide - shades of blue and blue; lead chromate and chromium - pink, bright red and brown. According to the composition of the enamel is divided into transparent, translucent and deaf, or opaque. The firing of the enamel applied to the product, depending on its composition, is performed at a temperature of 600 to 800 "C. The first appeared in Ancient Egypt in the 2nd millennium BC. The emergence of this technique, apparently, is associated with accidental cracking and melting of small inserts from colored glass, placed between golden partitions.Despite the fragmentary information, it can be argued that in the Eastern Mediterranean, enamel was already known by the middle of the 1st millennium BC The development of scientific knowledge in the leading center of European culture of the Middle Ages - Byzantium, led to the appearance in the 7th century. cloisonné enamelling techniques Byzantine enamellers quickly reached amazing perfection. cloisonne enamel was performed on a thin, usually slightly convex gold plate. With the help of a template, the master made an impression of a tray - a kind of miniature bed for enamel. At the bottom of the tray, the thinnest ribbons-partitions were soldered with an edge, “outlining” the clear contours of future images; they were filled with enamel mass. Then the enamel plate was fired and finally polished. The color scheme was distinguished by juiciness and richness. Cloisonne enamel was used to decorate headdresses, plates with it were sewn onto the ceremonial clothes of secular rulers and church hierarchs, they were preserved in abundance on the salaries of icons and church books. A remarkable monument of the work of Byzantine and Italian enamellers of the XII century. is the golden decoration of the altar barrier of the Cathedral of St. Mark in Venice.

Scanned enamel, in which colored enamels fill the contours formed by filigree (filigree), was very popular in the art of China, Transylvania (the northwestern part of modern Romania) and Italy in the 15th-17th centuries. Around the middle of the XVI century. this technique was used by Russian masters in Moscow, the cities of the Russian North and Veliky Novgorod. The best of such works were made in the royal workshops of the Armory. Among them is the gospel frame ordered by Ivan the Terrible for the Annunciation Cathedral in the Moscow Kremlin. The colors of the enamels here echo the pure deep tone of cornflower blue Ceylon sapphires. In the 17th century, in Moscow, the leading center of artistic crafts, especially exclusive and diverse enamel works were created. In the Moscow Posad, preference was given to soft blue-green enamels. She was used to color the patterns of herbs on caskets, bowls and boxes for rouge, which existed not only in the boyars' chambers, but also in the homes of wealthy citizens. This pattern was enlivened by miniature silver overlays in the form of stars and rosettes, they were complemented by drops of a white-enamel pearl. In our catalog of expensive gifts you can buy jam with amethysts.

Engraving (guilloche)

In the Baroque and Rococo era, enamel became one of the leading elements of artistic decor. Enamels on an engraved surface, painted enamels, juicy miniatures adorn snuffboxes, watches, rings, toilet boxes and fragrances in abundance. On them we see magnificent garlands of flowers, charming compositions on historical and biblical subjects, and even battle scenes. Small enamel masterpieces delighted contemporaries with the liveliness of colors and richness of shades. The wide recognition of the miniature in Russia led to the establishment in 1779 of an enamel painting class at the Academy of Arts. In the era of historicism, the motifs of enamel on filigree and carving products of pre-Petrine Rus' were revived. Ornaments taken from handwritten books appeared on a wide variety of items - from ceremonial, gift utensils and caskets to miniature jewelry. They were carried out by a number of workshops, among which the firms of I. Gubkin, P. Ovchinnikov, I. Khlebnikov became especially famous. During the years of unprecedented flourishing of enamels, their palette expanded fantastically. Faberge, for example, has almost one and a half hundred colors and shades! At the end of the 19th - beginning of the 20th century. many domestic and foreign masters preferred guilloché enamel. For the firms of L. Cartier, C. Faberge, I. Britsyn and others, things with guilloche enamel have become a kind of calling card. The silky sheen of the engraved pattern, applied by a special machine and covered with transparent or translucent enamel, created an enchanting effect. Gold and silver with guilloche enamel - from cufflinks and ladies' cigarette cases to table clocks and photo frames - were considered a kind of symbol of elegance. Guilloche enamel(guilloché enamel) is a technique of covering several layers of transparent colored and colorless enamel on a metal surface, previously engraved with a special mechanical device, which causes a pattern in the form of thin wavy lines, scales, spirals, clearly visible through the enamel surface. In our catalog of expensive gifts you can order.

The leading jewelers of Europe - from the Parisians Lalique and Vever to the craftsmen of Moscow and St. window, or stained glass, enamels. Objects decorated with window enamel are especially elegant. Applied to a cut-out or openwork filigree pattern, they produce an effect similar to a stained-glass window when viewed against the light. Fragile and complex in execution, these products required exceptional accuracy from the craftsman, and therefore work with them was available only to selected firms.

Carving, engraving- the oldest artistic technique for processing metals, wood, bone and stone, known to mankind for thousands of years. It is based on the application of a linear pattern or pattern to the surface of the product. Over time, the craftsmen moved from planar carving to engraving, which made it possible to give the image three-dimensionality, three-dimensionality. In Russia, the engraving technique was mastered at the turn of the 17th-18th centuries. One of the outstanding carvers of that time was the master of the Tsar's Armory Vasily Andreev. Images or patterns applied with a cutter serve as the first stage of work on a product decorated with niello, but at the same time, the thread line is taken out somewhat deeper than usual.

blackening

blackening - an ancient way of decorating silver and gold products. Its essence lies in applying a liquid alloy (niello) to the engraved metal surface, which includes silver, copper, lead and sulfur. The color and luster of a black pattern or image can vary from velvety black to bluish-grayish black. Back in the 16th century in the Treatise on Goldsmithing, Benvenuto Cellini described several recipes for niello. Finely ground powder is diluted with a solution of borax, potash and table salt to the state of liquid sour cream. This mixture covers the pattern or background of the image. After firing at a temperature of 300-400 ° C, excess drips are removed from the product; this is followed by polishing, and then the black coating acquires its characteristic brilliance and clarity. Items decorated using this technique have been known since antiquity. They are mentioned by Pliny the Elder. In the Middle Ages, fine niello was made by masters of Byzantium, the Middle East, Italy, the Caucasus, and Ancient Rus'. Noble luxury distinguishes the work of "blackened craftsmen" who served in the workshops of the Moscow Kremlin in the 16th-17th centuries. The rhythmic ornament of grass curls, decorating the side of a golden dish weighing almost 3 kg, which served as a wedding gift from Ivan the Terrible to his second wife, Circassian Maria Temryukovna, goes back to revivalist motifs. According to legend, it was presented to the young queen after the wedding night: on it lay her new headdress - a woman's kika, which replaced the girl's kokoshnik and wedding crown. Blackening and large precious stones are perfectly combined, decorating a golden censer in the form of a single-domed church, granted by Tsarina Irina Godunova to the tomb of Moscow sovereigns - the Archangel Cathedral of the Kremlin to commemorate the soul of her husband, Tsar Fyodor Ivanovich. In the XVIII century. the art of niello engraving was clearly manifested in the works of the masters of Veliky Ustyug and Tobolsk. Niello graphics depicting monuments of ancient Russian architecture against the background of thick grasses, induced along deep carvings, adorns products created at the end of the 19th century. masters of the factories of the Moscow merchant Vasily Semyonov and in the workshops of the firms of P. Ovchinnikov and I. Khlebnikov. Here, as in the 18th century items, blackening on silver was combined with beautiful gilding. Today, this ancient technique has been preserved in the North Caucasus, in the village of Kubachi, and far in the north of Russia, at the famous Severnaya Chern factory in Solvychegodsk, where they create a variety of silver jewelry: bracelets, earrings, rings, pendants, luxurious dishes and religious objects. . In our catalog of expensive gifts, you can order our one of the most popular charka lots in the form of a hussar shako.

Chasing

Chasing- a type of cold metal processing. It consists in applying a relief to a workpiece by hitting a chasing (punch) with a hammer, the tip of which is made in the form of a ball, star, square, groove, etc. Malleable and ductile precious metals - gold and silver - are ideal for this type of work. Masters of Ancient Rus' used up to 450 stamps for various purposes: with the help of some, the background was given a matte texture, while others were applied with patterned borders. Goldsmiths widely used chasing until a stamp was invented, which accelerated and reduced the cost of working on products. Along with chasing, embossing was also often used - a technique for processing metal to obtain relief images on its surface by extrusion.

notch- an ancient artistic technique of decorating with precious metals (gold or silver) bronze or steel products that contrast with them in color, including damask steel. In our catalog of expensive gifts, you can order an author's one with precious stones. This decoration method was used to decorate military and ceremonial weapons, armor, etc. The essence of the process is that notches are made on the surface of objects and gold or silver is stuffed into the resulting recesses. wire, creating the finest pattern of curls and stylized herbs, as well as images of animals or people. Often, commemorative inscriptions were made using the notch technique: the names of the owners, the signatures of the masters, or texts of a moralizing nature. Taushing was widely used in the XII-XVII centuries. It was brilliantly owned by the masters of Byzantium, the Middle East, China, Japan, the North Caucasus and Ancient Rus'. At present, this technique has been preserved in the arts and crafts of Italy, Spain, Iran, China and Japan. The artists of the Dagestan village of Kubachi, Tula, Izhevsk and Zlatoust are famous for it.

In our catalog you can buy everything. We also have stone-cut figurines, miniature sculptures in gold and silver.

Melnikov Ilya

Artistic processing of metal. Precious metals. Alloys and mining

Artistic processing of metal. Precious metals. Alloys and mining

Precious metals are metals that belong to the so-called noble group. These are gold, silver, platinum and platinum group metals. Such as ruthenium, palladium, iridium, osmium, rhodium.

They received the name "precious" for their high cost compared to other metals, and "noble" due to their high chemical resistance in many environments and beautiful appearance in finished products. Gold, silver, platinum, palladium, as well as alloys based on these metals are used for the manufacture of many art products and in jewelry.

From the book Inventions of Daedalus author Jones David

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From the book Materials Science: Lecture Notes author Alekseev Viktor Sergeevich

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From the book Artistic Metalworking. Ornamental and synthetic gemstones author Melnikov Ilya

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From the book Glass and its properties. Raw materials for glassmaking. Mixture preparation author Melnikov Ilya

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From the book Jewelry Materials author Kumanin Vladimir Igorevich

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From the book Fundamentals of Design. Artistic Metalworking [Tutorial] author Ermakov Mikhail Prokopevich

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From the book Artistic Metalworking. Enameling and artistic blackening author Melnikov Ilya

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From the book Artistic Metalworking. Corrosion and heat treatment author Melnikov Ilya

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From the book Water Filters author Khokhryakova Elena Anatolievna

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From the book Welding author Bannikov Evgeny Anatolievich

From the author's book

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Basic technological operations for metal processing

Casting
Gold, silver, bronze have high fusibility and are easily poured into molds. Castings follow the model well. Before casting, the master makes a wax model. Those parts of the object that must be particularly durable, such as handles of vessels, handles or latches, as well as ornaments and figures, are cast in sand molds. Complex pieces require several models to be made, as the different parts are cast separately and then connected by soldering or screwing. For repeating ornamentation, one form was enough, which was successively pressed into the sand several times, the best castings were obtained from copper models, because after punching they looked like works that had come out of the hands of a chaser. Electroplated castings were an invention of the 19th century.
Casting is one of the most ancient methods of metal processing. Archaeological excavations in Egypt and Babylon confirm that as early as 5,000 years before our era, people were able to cast metal.
In the field of production of art products, the following types of casting are now used, which differ in the following features.
For metal castings: iron casting, copper alloy casting, noble alloy casting.
According to the material and design of the molds: casting into temporary molds - earthen and shell molds, casting into permanent metal molds.
According to the nature of the models: with the loss of a model - wax casting, precision casting, according to a permanent model - earth casting.
According to the method of pouring molds with metal: conventional casting, centrifugal casting, pressure casting.

Artistic forging
Forging is one of the oldest methods of metal processing. It is carried out by hammer blows on the workpiece. Under its blows, the workpiece is deformed and takes the desired shape, but such deformation without ruptures and cracks is mainly characteristic only of precious metals, which have sufficient ductility, toughness, and malleability. The combination of these properties is called ductility. Cold forging lends itself to gold, silver, copper. This technique was widely used in ancient Rus' by goldsmiths who forged bowls, ladles and other products from ingots. During cold forging, the metal under the influence of impacts, changing its shape, quickly loses its plasticity, becomes denser, acquires a “hardening” and requires annealing for further processing. Therefore, the cold forging process consists of two alternating operations: metal deformation and annealing (recrystallization). In modern conditions, cold forging is rare in the field of artistic metal processing, mainly in jewelry production.
Difovka is an ancient method of cold working sheet metal, produced by direct hammer blows, under which it stretches, bends, sits down and, as a result, acquires the necessary shape. Difovka differs from forging in that it is made of sheet metal no thicker than 2 mm.
Dithing became a virtuoso art in the hands of the greatest ancient sculptors, such as Phidias, who dressed the statues of Athena and Hera in golden clothes, dithing them from thin golden sheets. Old Russian goldsmiths “beat out” bowls and goblets, ladles, decorated with chasing, engraving and precious stones from sheet gold and silver.

Chasing- this is a very peculiar, most artistic and at the same time labor-intensive production technique. Precious metals can be rolled into a thin sheet, then the shape of the object takes on its shape in a cold state with the help of accelerating hammers. Often an artistic product is processed on a base (lead or resin pad), which is selected depending on the degree of malleability of the metal. With short and frequent hammer blows with constant pressure and rotation, the metal is tapped until the desired shape is obtained. Then they move on to chasing (knocking out decor). The decor is knocked out with the help of chasers (steel rods of a certain profile). Products forged from a single piece of workpiece are the highest works of art. It is easier to work with two or more pieces of workpiece, which are then soldered to each other.
Technical perfection and plastic effect in high chased relief (especially in the presence of figures) was achieved in the Middle Ages by French and German goldsmiths, in the 4th century by Italian, and at the end of the 16th century by German masters. Thus, even then the limits of what was possible for this technique were reached. Later, a similar decor was cast and soldered. Even in ancient times, chasing on a solid model was used, especially for making figures. A gold or silver leaf was accelerated over a bronze or iron model and then removed from it. It developed further in the 18th and 19th centuries. For example, embossed products of the Novgorod chasers of the 11th-12th centuries of a cult nature (icon frames, etc.) have been preserved, in which the features of Russian and Byzantine art are uniquely combined. These are not only ornamental compositions made by chasing from a sheet, but also chased cast figures. Samples of chased art of Vlady-Miro-Suzdal Rus belong to this time. By 1412, the work of the master Lucian (folder), made by chasing with niello, as well as the work of Tver jewelers, made by chasing on silver casting, belongs. Chasing in high relief was made by Greek masters in Moscow, and chased ladles and bowls - in Novgorod. Chasing flourished especially in the 16th century, in Yaroslavl it was combined with carving and engraving, in Nizhny Novgorod it was enriched with cast sculptural details. Novgorod chasers began to use embossing with a conferred background. The flourishing of chased art continued into the 17th century. New techniques and artistic features appeared: from the second half of the 17th century and from the beginning of the 18th century
In Novgorod, chasers use a slotted ornament; in Kostroma, flat, crushed chasing develops, alternating with casting and carving; in Yaroslavl, chasing reaches a special pomp and is colored with colored enamel.
Artistic chasing is divided into two independent types of work, which have qualitative differences in production technologies.
1. Chasing from a sheet.
2. Chasing by casting or defense.
In the first case, a new work of art is created from a sheet blank by means of embossing, in the second, they only reveal and complete an art form that has already been cast in metal (or cut out of metal using the defensive technique).
Casting or armor chasing is used in cases where it is necessary to obtain a particularly clear and distinct embossed form. They mint mainly castings obtained by casting in earthen molds. Modern new types of casting (die casting, precision) do not require chasing, since the castings are very clear. When chasing, it is necessary to correct casting defects: shells, non-clay, as well as outgrowths, flash and other defects that result from the distortion of the flasks or from shedding of the earthen form, or at the site of metal potholes, from impact and erosion of the metal jet. In these cases, there are noticeable protrusions on the castings.
Basma (embossing) is a kind of development and improvement of coinage. Instead of repeated strikes with a chasing, necessary for sculpting a complex shape, basmen boards-matrices are used.
The advantage of embossing in comparison with embossing is the speed of production of products, as well as significant savings in precious metal, since basma, compared to embossing, is carried out on a material of much thinner thickness.
In ancient Russian art, the embossing technique originated in the pre-Mongolian period (X-XI centuries) and was used to produce relief blanks for niello and enamel. Basma has been developing since the 15th century, but it reached its peak in the 16th and 17th centuries. For embossing basma, first of all, a basma board (matrix) is made. It is a low monolithic metal relief with soft smooth lines without sharp corners and sharp protrusions that break through thin metal during embossing. The total height of the relief on ancient basmas does not exceed 1-2 mm, but by the 17th century (especially at the end of it) it sometimes reaches 5-6 mm (on large basmas). The embossing process is as follows: a thin sheet of metal is placed on the matrix, the thickness of which does not exceed 0.2-0.3 mm, previously annealed and bleached. Then a lead pad is applied on top. This lead cushion is struck with a wooden mallet. Under the action of force, the lead is pressed into all the recesses of the matrix, exactly repeating its entire relief. The metal sheet, sandwiched between the matrix and the lead gasket, undergoes the same deformations. After embossing, the lead is removed and the basma is removed from the matrix - a thin relief that very accurately reproduces all the details of the matrix, including the texture. Basma is somewhat different from the matrix in the clarity of the pattern. On Basma, it turns out to be softer, as if slightly smoothed. This difference is due to the thickness of the sheet used for embossing. The thicker the sheet of metal, the greater the discrepancy.
In ancient Russian art, basmas were used for binding various items, both cult and secular: iconostases, frames and backgrounds of icons, book bindings, chests, and caskets. Basmas were performed with portrait images or with ornamental ones. Basmas with a repeating ornament were especially often used. To obtain such an ornament, only one rapport was made on the matrix, and then in the process of making basma, after each stamping, the workpiece moved by the amount of rapport and was imprinted again, such joints are clearly visible on the finished basma. By the presence of joints, it is easy to distinguish embossing from embossing.

metal plastics
Metal-plastic is one of the ancient types of artistic processing of metals. This technique was used by artists of the Middle Ages, but became especially widespread at the end of the 19th - beginning of the 20th century, when products made using this technique became fashionable. In Russia, at the All-Russian Handicraft Exhibition in St. Petersburg in 1913, various metal-plastic works were exhibited: ladles, caskets, frames. Due to the simplicity and accessibility of techniques, it was included in the curriculum of the Soviet school in the 20s. However, then this technique was forgotten, and only recently interest in it has increased again.
Works of art made in this technique resemble chasing from a sheet in appearance, but in essence they differ significantly, primarily in the thickness of the sheet metal.
Sheets with a thickness of 0.5 mm or more are used for embossing, and foil up to 0.5 mm is used for metal-plastic. However, the main difference between metal plastics is in the technological process itself and in the set of tools. In embossing, the form is formed by hitting the embossing with a hammer, and in metal-plastic, the form is molded by smooth deformations carried out by special tools resembling sculptural stacks.

Engraving
Engraving is one of the oldest types of artistic metal processing. Its essence is the application of a linear pattern or relief to the material using a cutter. In the technology of artistic engraving, one can distinguish between:
- planar engraving (two-dimensional), in which
surface only;
- armored engraving (three-dimensional).
The technique of planar engraving is widely used in the artistic processing of metals. Its purpose is to decorate the surface of the product by applying a contour drawing or pattern, complex portrait, multi-figure or landscape tone compositions, as well as the execution of various inscriptions and type works. Engraving is used to decorate both flat and three-dimensional products.
The possibilities of planar engraving are very wide: drawings, graphic works made with a cutter on metal are even more subtle and perfect than drawings made with a pencil or pen.
Plane engraving, also called gloss engraving or engraving for appearance, also includes niello engraving, which technologically differs from ordinary engraving only in that it is performed somewhat deeper, and then the selected pattern is filled with niello.
At the end of the 18th century, machines began to be used for engraving, covering the entire surface of the object with uniform lines, regular circles and arcs. This technique - guilloche - was transferred from wood turning at the beginning of the 19th century and completely replaced handicraft engraving. It was used for engraving watch cases, snuff boxes, etc.
Engraving engraving - a method in which a relief or even a three-dimensional metal sculpture is created. In frontal engraving, two options are distinguished: convex (positive) engraving, when the relief pattern is higher than the background (the background is deepened, removed), in-depth (negative) engraving, when the pattern or relief is cut inside.

Etching
This is another technique related to graphics. As in etching, the object was covered with resin or wax, and then the decor was scratched onto it. When the product was immersed in acid or alkali, the scratched places were etched, and the surface around them, often damaged by the intervention of the tool, became dull. So there was a very shallow and gently emerging relief. This technique was used in earlier times for inscriptions on cups, but reached its peak in the 16th century.

Decoration technique.

Filigree- a kind of artistic metal processing, which has occupied an important place in jewelry since ancient times.
The term "filigree" is more ancient, it comes from two Latin words: "phylum" - thread and "granum" - grain. The term "scani" is of Russian origin. It originates from the Old Slavic verb "skati" - to twist, twist. Both terms reflect the technological essence of this art. The term "filigree" combines the names of the two main primary elements from which the typical filigree production is produced, namely, that the wire used in this art form is twisted, twisted into cords.
The thinner the wire and the tighter, steeper it is twisted, the more beautiful the product, especially if this pattern is complemented by granulation (tiny balls). The most ancient monuments belong to the second millennium BC, found in the countries of Asia Minor, Egypt. The most ancient works of filigree art are characterized by the predominance of granulation, and smooth and twisted wire is rare.
Items decorated with grain are also characteristic of Scythian art.
The grain here remains a typical motif for filigree products of the 10th and 11th centuries. Such items were sometimes almost completely covered with fine grains, and on a small object there were up to six thousand grains with a diameter of no more than 0.5 mm.
From the 12th century, the wire pattern began to predominate in filigree, and the grain became of secondary importance. The ornament is built from twisted wire in the form of spiral curls. All these works continue to retain their soldered, or background, character, that is, the pattern is soldered onto sheet metal.
In the 13th century, the variety of filigree patterns increased. Openwork and multifaceted filigree appears.
The Tatar-Mongolian yoke slowed down the development of Russian culture for a long time, many filigree techniques were lost, in particular the method of soldering the smallest gold grain, which was only recently rediscovered by Professor F.Ya. Mishukov, who established that ancient masters used mercury as solder. It dissolved gold in itself, forming an amalgam, and then, when heated, the mercury evaporated, and the balls were firmly connected to the background.
The 15th and 16th centuries are characterized by a new flourishing of scanned art in Rus'.
History has preserved for us the names of the jeweler-scanner Ambrose (XV century) and Ivan Fomin.
In the 11th and especially in the 12th centuries filigree becomes polychrome. The composition includes many non-metallic materials (enamel, glass, precious stones).
Until the 17th century, the production of filigree products was concentrated in royal, princely and monastic workshops. In the 17th century, independent craftsmen appeared, and the production of products designed for a wider range of consumers began. There is a division of labor.
In the 18th century, along with unique openwork products, often with the use of crystal and mother-of-pearl, household items became widespread: toiletries, boxes, vases. As a decorative motif, granulation reappears.
At the end of the 19th and the beginning of the 20th centuries, filigree products were already produced by large factories (Ovchinnikova M.P., Khlebnikova I.P., Sazikova I.P.) in large series and a varied assortment - these are mainly church utensils, expensive dishes, toilet utensils . Technological methods during this period reach great perfection and professional performance, are distinguished by special accuracy and subtlety.
Particularly characteristic of this time was the flourishing of relief-laced filigree, used for making settings for icons, where the clothes of saints were made of filigree, landscape elements: clouds, trees, rocks. The revival of openwork filigree with enamel, the so-called "window" enamel, belongs to the same period.
In modern production, filigree products are made from start to finish by hand or with the help of simple devices: this is the specificity of this technique.
There is a wide variety of types and varieties of filigree, which are classified as follows. Brazed filigree, when a pattern of wire, as well as granulation, is soldered directly onto sheet metal. Soldered filigree has the following varieties:
- background, or deaf filigree, the simplest pattern is soldered onto sheet metal, sometimes the background is additionally chiseled;
- perforated, or cut filigree, in which, after soldering the pattern, the background is removed by sawing;
- embossed filigree on chasing - a filigree pattern is soldered onto a relief prepared in advance by chasing;
- soldered filigree with enamel, or cloisonné enamel, in which
after soldering the filigree, all spaces between the partitions formed
filigree, filled with enamel.
Openwork filigree is a processing in which a pattern consisting of elements made of wire is soldered only to each other, without a background, forming, as it were, a metal lace, and the grain used in these cases is soldered onto this lace. Openwork filigree has the following varieties:
- flat openwork filigree - the whole object is a flat (two-dimensional) lace formed by wire parts soldered together in one plane;
- openwork filigree with enamel, or "window" enamel, - openings, cells between scanned details are filled with transparent translucent enamel, forming, as it were, a miniature colored stained glass window
- sculptural-relief openwork filigree - the product is a sculptural, three-dimensional relief (sometimes high relief), formed from openwork filigree;
- multifaceted, or complex filigree, - filigree pattern, consisting of
two or more plans soldered one on top of the other, that is, when a new pattern lying in another plane is superimposed and soldered on the lower pattern, which serves as a background, a third plan can be built on it, etc.
Volumetric filigree. It includes three-dimensional objects made by scanning technique: vases, goblets, trays, caskets, boxes, three-dimensional images of birds, animals, and architectural forms. Such products are made from separate parts, which are then assembled into a whole composition.
At present, filigree products can be replicated by casting and electroforming. Stamps can only be used to reproduce the background filigree.

Enameling
Enamel is a vitreous solidified mass of an inorganic, mainly oxide composition, formed by partial or complete melting, sometimes with metal additives, applied to a metal base.
The earliest known enamel jewelry has been found in Greece and dates back to 1450 BC. On the island of Cyprus, two pendants in the form of a flower, made in the technique of filigree enamel, were found, made around the 10th century BC.
Enamel products. Late XIX - early XX centuries.
Egyptian influence is clearly seen in the form and technique of execution.
A diadem with leaves and flowers decorated with enamel was found in Azerbaijan (7th century BC). From the first half of the VI century BC. Greek jewelry was covered with white, dark blue, dark green and pale turquoise enamel.
From the 3rd century BC small, in the form of a drop of metal pendants, completely covered with enamel, have come down to us. They were probably immersed in molten colored glass.
Despite fragmentary information, it can be argued that in the eastern Mediterranean already in the first millennium BC. they melted glass on metal and that Greek ornaments were decorated with colored enamel. Despite the fact that these first attempts corresponded technically to enameling, they were still only a form of polychrome enrichment of metal decoration inlaid with polished plates of precious stones, smalt or glass, glued into recesses or soldered partitions.
The transition from inlay to enamel could take place where the technical prerequisites for metalworking and the manufacture of low-melting glass were sufficiently well developed. If we look for the origins of enamelling, then we should not talk about the first piece of glass welded onto metal, but about the mass production of metal products in combination with colored glass.
Egyptian inlays made of ornamental stones on the principle of cloisonné enamels were already known during the 5th dynasty (from 2563 to 2423 BC). Figurative images, written signs and ornaments were made on gold in the form of depressions and then filled with precious stones and smalt. The decoration with smooth undivided colorful planes helped the understanding of ancient Egyptian painting. It was this technique that was of great importance for the further development of jewelry, as it prepared the enrichment of precious metal with non-ferrous finishing materials.
The cells were a stepping stone both for the appearance of settings for stones, and for later cloisonné and champlevé enamels. Cells were made by soldering partitions, and ornamental stones and smalt were processed in the shape of cells and fixed on resin, later they were fixed in cells with glue. So, there was still a small step to real enamel: it was necessary to heat up the entire product and melt the glass powder until a smooth surface was obtained. Only in the VI century BC. the Greeks began to systematically fuse enamel on their gold jewelry. With this, they created the basis for the color finish of metal with stone. Unlike Greek, Egyptian jewelry always remains strictly planar: gems placed in a recess stand on the same level with ceramics and colored glass plates as mosaic components of the overall composition.
Greco-Roman jewelry is distinguished by pronounced plasticity. It is accentuated by accentuated color effects, both single colored gemstones and fused colored glass.
Already in the 5th century BC. the Celtic tribes who inhabited part of France and Britain developed a completely different type of enamel - champlevé enamel. At first it was only fused opaque red glass, which was used instead of coral inserts that were common at that time. Opaque enamel of saturated color was pressed tightly against each other, separated by narrow partitions. Jewelry, vessels, weapons, parts of horse harness were decorated in this way.
In order to color enrich expensive jewelry, German jewelers (from the 4th to the 7th centuries) used colored stones and colored glass as inserts, with preference given to red almandine. At the same time, thin almandine plates were polished very well. Almandines in some products are fixed with green glass plates in a grid of golden partitions, but without a base. On the reverse side, it is clearly seen that the glass plates are soldered into frames. So, we can already talk about "window" enamel.
The development of science and technology led to the appearance in the 8th century of Byzantine cloisonne enamel, which quickly reached the highest perfection, which was used not as a means of imitation of stones, but as an independent artistic technique, out of touch with the past.
It is Byzantine enamels that are considered classic examples of enamels, and not Celtic-Roman champlevé enamels that are completely different in execution, which appeared 500 years earlier, and non-Egyptian stone inserts according to the principle of cloisonné enamels.
The processing of precious metals was highly developed in Late Antique Byzantium. There were technical prerequisites for combining glass and metal. Thus, Byzantine enamel developed in a completely new quality as a pictorial medium. The heyday is considered to be the period until the XII century.
The experience of Byzantium had a decisive influence on the development of enamel technique in Europe in the Middle Ages. At the beginning of the 10th century, an original technique of cloisonné enamel was developed in Kievan Rus. Quite a few examples of enamel and filigree work of that time have survived, striking in the subtlety of technical and artistic performance. From thin gold threads-wires on the surface of the object, a pattern was drawn, the smallest cells of which were filled with enamel of various tones.
Since the 12th century, champlevé enamel has been recognized as an artistic method of decorating church utensils with color figurative and ornamental motifs. The most significant workshops were located on the Rhine and in the French city of Limoges. Limoges developed into a leading center for the mass production of church utensils using various types of enamel. He held the primacy until the 16th century. The next stage in the development of this technique, dating back to the beginning of the 14th century, was enamel on chased relief. The figures were made in flat relief, transparent enamel was applied over the entire surface. The image mysteriously shone through the enamel, the plasticity of which is further emphasized by layers of enamel of different thicknesses.
The era of the Renaissance (renaissance) reached its climax on the economic basis of emerging capitalist relations. It has received especially great development in all areas of handicraft production. The need to emphasize one's social position with luxurious clothes and expensive jewelry is especially characteristic of the second half of the 15th century. In comparison with examples of Gothic art, the lively diversity of jewelry design is striking. A relatively small area is dominated by an oversaturated ornament, partially covered with enamel, with inclusions of colored stones and pearls, enamel relief figures. Volumetric relief enamel became the dominant technique of enamelling.
At the beginning of the 15th century, a completely new technique appeared - painted enamel. With finely ground colored enamels, the image was applied to a single-color enamel base, and the paints were applied without separating partitions. There were several workshops in Italy where this method was used, but Limoges became the center for the development of new technology in the 15th-16th centuries. In the 16th century, the typical technique of the Limoges masters developed - grisaille enamel, that is, enamel in gray tones. On a plate primed with black or dark enamel, an image was applied with white enamel. Depending on the thickness of the layer, the dark color shines through more or less, resulting in gray undertones. Another method was based on graphic techniques: the black base was covered with a thin layer of white enamel, scratched
in a moistened state, the drawing and gave the image plasticity through shading. After that, the enamel was fired. Initially, only scenes from the Bible were depicted in the technique of Limoges enamel; in the middle of the 16th century, motifs of the Italian Renaissance came to the fore. Then Limoges enamel began to cover various utensils. A special group is made up of convex vessels with a characteristic pattern, the enamel coating of which is usually called Venetian enamel, since it was believed that it was developed in Venice. We are talking about hammered and enameled vessels, gold bouquets, rosettes, leaves are fused into the enamel. These products appeared in the first half of the 16th century.

Decorative processing
The description of the decorative finish of the product should contain information about the location, individual dimensions, quantity, and characteristics of the elements of artistic processing. Typical elements included in the general description are given below.
1. Matting.
2. Blackening.
3. Oxidation.
Matting
A matted, or textured, surface of products is considered a surface that differs from polished, bearing a decorative load.
The texture of the surface can be small-pitted, small-hatched, matte. The effect of combined texture processing with gloss is most often used. Textured surface areas are obtained using a casting crust of products, a polished surface (after sandblasting the working surface of the stamp), using etching in various acid compositions, mechanical matting (with a burr, ground pumice, brushing).

blackening
Niello (a fusible alloy of composition: silver, copper, lead, sulfur) is applied to a product prepared for niello, that is, with recesses with an engraved pattern. The depth of the pattern within 0.2-0.3 mm depends on the size of the product. The surface of the product, not covered with black, must be polished, without scratches, scratches and other defects.

Oxidation
Products made of silver and silver-plated are oxidized (treated) both chemically and electrochemically. The processes of chemical and electrochemical colorless oxidation are carried out in solutions and electrolytes, the main component of which is potassium dichromate. In the process of color oxidation, products are dyed with a variety of shades: blue, black, gray, dark brown, etc. Oxidized products are brushed with soft brass brushes to give the films a beautiful shine. The oxidized surface must be evenly matt, without any difference in color shades.

Electroplating
In the jewelry industry, gold, silver, and rhodium are used as electroplating coatings. On electroplated coatings there may be slight traces of contact points with conductive devices that do not disturb the coating layer and do not worsen the appearance of the product.

List of used literature.
Nona Dronova. Handbook-encyclopedia. "Jewelry"
Publishing House Jeweler.
M. M. Postnikova-Loseva, N.G. Platonova, B.L. Ulyanov "Gold and silver work of the 15th-20th centuries."

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