home › Tests › Growing ruby crystals at home using the Verneuil method. M

Growing ruby crystals at home using the Verneuil method. M

Related to "About Chemistry"

Growing ruby crystals at home

Attention: this article is part of a more general article: About chemistry in which it is used.

Synthetic gemstones are virtually indistinguishable from natural stones in their chemical composition and physical properties. The whole problem turns out to be that among natural gems, not all of them have sufficient purity and other jewelry qualities. in order to be honored to be presented in jewelry stores, and in the conditions of laboratory or factory production, the technological process can be debugged so that all crystals grown in the laboratory will have almost the same jewelry characteristics. And in production they are much cheaper than their "colleagues" of the same quality, mined in deep and life-threatening working mines. In addition, deposits of certain minerals are not scattered in abundance evenly over the entire globe, but are concentrated, as a rule, in a few places.

Further thought flowed by analogy with stained-glass windows and mosaics. If on the Internet I came across offers for these services from large reputable companies with solid production areas and cash flow, then, I then asked myself why it is impossible to make small stained-glass windows (inserts in interior doors, wall lamps, etc.) literally at home desk?

I studied the technology, puzzled over how it can be simplified for home use, conducted a certain number of experiments - and got the result!

Similarly, Alexander and I began to creatively rework the idea of growing gemstone crystals at home. We studied (at an introductory level) different methods, and settled on the method of the French scientist Auguste Verneuil, who created more than 100 years ago an original technique and equipment that allowed grow ruby crystals weighing 20-30 carats in 2-3 hours. This was an outstanding achievement of science and technology, not only because it made it possible to artificially produce such a valuable material in the required quantities, but also because it opened up prospects for the synthesis and growth of crystals of other precious stones.
The success of O. Verneuil was preceded by almost half a century of research on the synthesis of ruby. The first mention of ruby synthesis is associated with the name of Mark Gooden. In 1837, he obtained microscopic crystals of ruby by fusing aluminum-ammonium alum with an admixture of potassium chromate in a clay crucible covered with lamp soot (soot) in a blast furnace. small corundum and ruby crystals were later synthesized by J. Ebelman, X. Senorman, Clary and other researchers. However, all these works had no practical value. Separately, it should be noted the studies of E. Fremy and E. Fail, who for the first time tried to obtain corundum crystals from a solution in a melt. They used lead oxide as a solvent for alumina. The addition of chromium oxide or cobalt oxide to the initial mixture made it possible to obtain red and blue crystals, respectively. Some of them turned out to be suitable for watch bearings and jewelry cutting.
Then, in the 80s of the 19th century, the so-called "reconstructed", or Siamese rubies, which are fused fragments of natural crystals, appeared on the gemstone market. French scientists achieved the best results in obtaining "reconstructed" rubies. They designed an apparatus that included a centrifuge, a clay (or platinum) crucible and a rotating gas (oxy-hydrogen) burner. sintering It was carried out by successively lowering several fragments of crystals of natural rubies into the crucible and made it possible to obtain stones weighing up to 10 carats. Although the resulting stones could not be attributed to synthetic, nevertheless, after the method of their manufacture became known, interest in them fell sharply. And the "reconstructed" rubies became completely uncompetitive after the appearance of synthetic Verneuil rubies. The first crystals were obtained by O. Verneuil together with E. Fremy from a melt of barium and calcium fluorides and cryolite with the addition of chromium oxide. In 1890, they donated to the Paris Academy of Sciences hundreds of sparkling crystals of differently colored corundum, which, according to the conditions of obtaining, could not be cheaper than natural rubies. But already in 1892, O. Verneuil obtained the first results on the synthesis of corundum crystals from pure aluminum oxide. The studies were completed by him in 1902. The simplicity and reliability of the Verneuil method led to the rapid organization of the industrial production of these crystals, first in France, and later in almost all highly developed countries of the world.

The first figure shows the very principle of the Verneuil method (isn't it - everything looks quite simple!), And the second picture shows the Verneuil apparatus. It looks rather complicated, even at first it inspires some fear - they say, I would never do such a thing! But, these are false fears. After all, it should be remembered once again that the inventor created his technology more than 100 years ago!

Naturally, he did not have at his disposal those electrical and mechanical "tricks" that are available to any home master at the present time!

Here is the problem - how to simplify the Verneuil apparatus through the use of modern electrical components and mechanisms of wide availability and create a "kitchen" version of the apparatus.

And we succeeded!

In the near future, with the permission of Alexander, I will publish on this page more detailed information on the "kitchen" version of the Verneuil apparatus, when I prepare it.

So far, I can only say that using the Verneuil method, it is possible to grow crystals not only of ruby, but also of blue, white (transparent) and yellow topaz (as well as other shades if desired).

So, if you are interested, I advise you to return to this page after a while. And one more thing: I publish a detailed description of the "kitchen" version (with the consent of Alexander) as the main generator of the idea, and without any fear of competition from those enthusiasts who decide to follow this idea. The reason is very simple: at present, artificial precious crystals are grown in many countries of the world, but as soon as you go to a jewelry store, it will immediately become obvious that prices are still "biting". And the saturation of the market, apparently, is still very, very far away. And even after reading this information, there are several thousand enthusiasts, then with our "home" production, we all cannot make special "weather" in this market segment. Therefore, the results of our research can be published without fear of anything. On the contrary, if something like the "Association of Home Crystal Growers" appears on the net :-), then it will be even more interesting and useful for everyone, since, as you know, two heads are good, and two thousand - one can confidently assume - much better. And some of these heads may turn out to be much lighter, and their ideas will help everyone who is interested to further simplify and improve the device, and turn it from a "kitchen", for example, into a "bedside table" :-).

Now a few words about the economic efficiency of the project. To grow a ruby crystal weighing 20-30 carats (4 - 6 grams!) It will take 3 hours and 3 kWh of electricity. Calculate how much it costs in your area. Think. that the figure will be less than 10 rubles. The cost of 6 grams of aluminum oxide powder and 0.2 grams of chromium oxide generally cannot cost more than 50 kopecks.

So, if you "push" even a rough crystal to an interested jeweler, you don't need to have a Soros head to realize that the profit from the transaction will be very solid. Well, if you make your wife or girlfriend happy with rubies and topazes, then the psychological dividends from such "investments" cannot be counted at all! :-).

For growing crystals and in general for chemical experiments at home, chemical reagents are needed. In addition to the base - a fairly pure aluminum oxide, various additive salts are needed that give the crystal a color. Today there are no problems with chemical reagents, at http://chemprom.com you can choose and order what you need in the familiar interface of the online store. Here you can also get advice on reagents, recommendations on completing your home laboratory.

For now, I say goodbye.

For more information on making a homemade ruby crystal grower (and also, sapphire crystals - white, blue and yellow) is described in my books on the subject. Books can be found by returning to the page:

All questions you can ask me by e-mail:
http://rubin-bmm.narod.ru/ [email protected]

With respect and wishes of success and prosperity
Mikhail Babin

Synthetic gemstones are virtually indistinguishable from natural stones in their chemical composition and physical properties. The whole problem. It turns out that among natural gems, not all of them have sufficient purity and other gem qualities to be honored to be presented in jewelry stores, and in laboratory or factory production, the technological process can be debugged to such an extent that all crystals grown in the laboratory will have almost the same jewelry characteristics.

And in production they are much cheaper than their "colleagues" of the same quality, mined in deep and life-threatening working mines. In addition, deposits of certain minerals are not scattered in abundance evenly over the entire globe, but are concentrated, as a rule, in a few places.

Growing ruby crystals at home

Further thought flowed by analogy with stained-glass windows and mosaics. If on the Internet I came across offers for these services from large reputable companies with solid production facilities and cash flow, then I asked myself why it was impossible to make small stained-glass windows (inserts in interior doors, wall lamps, etc.) literally on your desk?

I studied the technology, puzzled over how it can be simplified for home use, conducted a certain number of experiments - and got the result!

The success of O. Verneuil was preceded by almost half a century of research on the synthesis of ruby.

The simplicity and reliability of the Verneuil method led to the rapid organization of the industrial production of these crystals, first in France, and later in almost all highly developed countries of the world.

The first figure shows the very principle of the Verneuil method (isn't it - everything looks quite simple!), And the second picture shows the Verneuil apparatus.

The principle of operation of the Verneuil method

Verneuil apparatus

It looks rather complicated, even at first it inspires some fear - they say, I would never do such a thing! But these are false fears. After all, it should be remembered once again that the inventor created his technology more than 100 years ago!

Naturally, he did not have at his disposal those electrical and mechanical "tricks" that are available to any home master at the present time!

It was on this problem - how to simplify the Verneuil apparatus through the use of modern electrical components and mechanisms of wide availability and create a "kitchen" version of the apparatus - that we began to work.

And we succeeded!

The site http://rubin-bmm.narod.ru contains more detailed information on our "kitchen" version of the Verneuil apparatus.

Using the Verneuil method, you can grow crystals not only of ruby, but also of blue, white (transparent) and yellow topaz (as well as other shades as desired).

I am publishing a detailed description of the "kitchen" version (with the consent of Alexander) as the main generator of the idea and I am not at all afraid of competition from those enthusiasts who decide to follow this idea. The reason is very simple: at present, artificial precious crystals are grown in many countries of the world, but as soon as you go to a jewelry store, it will immediately become obvious that prices are still "biting". And the saturation of the market, apparently, is still very, very far away. And even if after reading this information there are several thousand enthusiasts, then with our "home" production, we all cannot make any special "weather" in this market segment. Therefore, the results of our research can be published without fear of anything. On the contrary, if something like the "Association of Home Crystal Growers" appears on the net :-), then it will be even more interesting and useful for everyone, since, as you know, two heads are good, and two thousand - one can confidently assume - much better. And some of these heads may turn out to be much lighter, and their ideas will help everyone who is interested to further simplify and improve the device, and turn it from a "kitchen", for example, into a "bedside table" :-).

Now a few words about the economic efficiency of the project. To grow a ruby crystal weighing 20-30 carats (4-6 grams!), it will take 3 hours and about 3 kWh of electricity. Calculate how much it costs in your area. Think. that the figure will be less than 10 rubles. The cost of 6 grams of aluminum oxide powder and 0.2 grams of chromium oxide generally cannot cost more than 50 kopecks.

So if you, dear reader, offer even an uncut crystal to an interested jeweler, then you don't need to have a Soros head to understand that the profit from the transaction will be very solid. Well, if one of the handmade men makes his wife or girlfriend happy with rubies and topazes, then the psychological dividends from such "investments" cannot be calculated at all! :-).

A few more words about the legal legality of such proceedings. Of course, we still have to thoroughly consult with lawyers, but the law of the Russian Federation “On PRECIOUS METALS AND PRECIOUS STONES” that I reviewed (last amended on July 18, 2005 N 90-FZ) says very specifically that the object of regulation of this law are “precious stones - natural diamonds, emeralds, rubies, sapphires and alexandrites, as well as natural pearls in raw (natural) and processed form. Unique amber formations are equated to precious stones in the manner established by the Government of the Russian Federation. This list of gemstones can only be changed by federal law.”. Specially singled out the word - "natural". Nothing is said about synthetics.

Artificial stones have long gained popularity in jewelry. Indeed, for a jeweler, the value of a stone is determined not only by its scarcity in nature. A number of other characteristics play an important role:

color;
light refraction;
strength;
weight in carats;
the size and shape of the edges, etc.

The most expensive artificial gemstone Fianit (synonyms: daimonsquay, dzhevalit, zirconium cube, shelby). Its price is low - less than $ 10 per 1 carat (0.2 grams). But it is worth noting that with the increase in carats, the price rises exponentially. For example, a 10 carat diamond costs 100 times more than a 1 carat diamond.

Artificial gemstone crystals can be grown at home. Most of these experiments do not require special training, you do not need to equip a chemical laboratory and even purchase special reagents.

To gain experience in growing crystals, start small. We will share the technique of growing beautiful crystals from anything you can actually find in your own kitchen. You do not need additional equipment at all, because everything you need is definitely on the shelves. We will also consider the technology of growing artificial rubies at home!

How to grow ruby crystals synthetically?

Growing ruby crystals can even be a home business option. After all, beautiful synthetic stones are already in great demand among buyers today, so if the project is successful, they can bring you a good profit. Synthetically grown stones are used by jewelers and are also widely used in engineering.

Ruby crystals can be grown according to the standard method, choosing the right salts. But this will not be as effective as in the case of salt or sugar, while the growth process is much longer in duration. Yes, the quality is questionable. After all, a natural ruby on the Mohs hardness scale is second only to Diamond, occupying an honorable 9th place. Naturally, when it comes to business, in most cases they use a different method, developed more than 100 years ago in France.

You will need a special apparatus named after the inventor of this method, i.e. the Verneuil apparatus. With it, you can grow ruby crystals up to 20-30 carats in just a few hours.

Although the technology remains about the same. Salt of aluminum dioxide with an admixture of chromium oxide is placed in the accumulator of an oxygen-hydrogen burner. We melt the mixture, observing how the ruby actually grows "before our eyes".

Depending on the composition of the salt you have chosen, you can adjust the color of the crystals, obtaining artificial emeralds, topazes and completely transparent stones.

Working with the device will require your attention and some experience, but in the future you will get the opportunity to grow crystals that fascinate with their beauty, transparency and play of color. In the future, such masterpieces are well suited for cutting and polishing, respectively, can be used for their intended purpose.

It is worth noting that artificially grown crystals are not gems, so even if you decide to enter the business of growing them, this will not require you to additionally license.

The design of the device is simple, you can easily do it yourself. But on the Internet there are already enough craftsmen offering drawings of the original installation, as well as its improved versions.

Kit for growing ruby crystals at home

The very principle of ruby production technology is quite simple and is schematically depicted below in the figure:

Understanding the principle of operation, any device no longer seems so complicated. One of the samples of the drawings of the Verneuil apparatus:

Using this technology, you can also grow other expensive artificial stones, such as Blue Topaz, etc.

Growing salt crystals at home

The easiest and most affordable experiment you can do is to create beautiful salt crystals. For this you will need a few items:

Ordinary rock salt.
Water. It is important that the water itself contains as little of its own salts as possible, and preferably distilled.
The container in which the experiment will be carried out (any jar, glass, pan will do).

Pour warm water into the container (its temperature is about 50 ° C). Add salt to the water and stir. After dissolution, add again. We repeat the procedure until the salt ceases to dissolve, settling to the bottom of the vessel. This suggests that the saline solution has become saturated, which is what we needed. It is important that during the preparation of the solution its temperature remains constant, does not cool down, so we can create a more saturated solution.

Pour the saturated solution into a clean jar, separating from the sediment. We select a separate salt crystal, and then place it in a container (you can hang it on a thread). The experiment has been completed. After a few days, you will be able to see how your crystal has grown in size.

Growing sugar crystals at home

The technology for obtaining sugar crystals is similar to the previous method. You can lower the cotton cord into the solution, then sugar crystals will grow on it. If the process of crystal growth has become slower, then the concentration of sugar in the solution has decreased. Add sugar to it again, then the process will resume.

Note: if you add food coloring to the solution, then the crystals will become multi-colored.

You can grow sugar crystals on sticks. For this you will need:

ready-made sugar syrup, prepared similarly to a saturated saline solution;
wooden sticks;
a little granulated sugar;
food coloring (if you want colorful candies).

Everything happens very simply. Dip a wooden stick in syrup and roll in granulated sugar. The more grains stick, the more beautiful the result will be. Let the sticks dry properly and then just move on to the second phase.

Pour the saturated hot sugar syrup into a glass, put the prepared stick there. If you are preparing multi-colored crystals, then add food coloring to the hot ready-made syrup.

Make sure that the stick does not touch the walls and bottom, otherwise the result will be ugly. You can fix the stick with a sheet of paper by putting it on top. The paper will also serve as a lid for the container, which will not allow any foreign particles to get into your solution.

In about a week, you will have wonderful sugar lollipops. They can decorate any tea party, delighting not only children, but also adults!

Growing crystals from copper sulfate at home

Crystals from copper sulphate are obtained in an interesting shape, while they have a rich blue color. It is worth remembering that copper sulfate is a chemically active compound, so crystals from it should not be tasted, and care must be taken when working with the material. For the same reason, only distilled water is suitable in this case. It is important that it be chemically neutral. Be careful and careful when handling blue vitriol.

In this case, the growth of crystals from vitriol occurs in fact according to the same scheme as the previous cases.

When placing the main crystal for growth in the solution, you need to make sure that it does not come into contact with the walls of the dish. And do not forget to monitor the saturation of the solution.

If you placed your crystal at the bottom of the vessel, then you should make sure that it does not touch other crystals. In this case, they will grow together, and instead of one beautiful large sample, you will get a mass of indistinct shape.

Helpful advice! You can independently adjust the size of the faces of your crystal. If you want some of them to grow more slowly, you can lubricate them with Vaseline or grease. And for the safety of the sky-blue handsome man, you can process the edges with a transparent varnish.

There are 3 weight categories of diamonds:

Small. Weight 0.29 carats
Average. Weight from 0.3 to 0.99 carats
Large. Diamonds over 1 carat.

Stones weighing 6 carats or more are admitted to popular auctions. Stones weighing more than 25 carats are assigned their own names. For example: "Winston" diamond (62.05 carats) or "De Beers" (234.5 carats), etc.

Values 7

A lot of myths have developed around jewelry with synthesized, that is, artificially grown stones and jewelry with imitation inserts. It's time to get rid of these delusions!

Subtleties of classification

Jewelry stones, created not by nature, but by man, can be divided into synthetic (synthesized) and imitations. The former have a natural, real-life analogue and completely coincide with it in color, composition, hardness and other physical and chemical properties. For example, rubies, emeralds, diamonds, sapphires are natural and synthetic. Lab-grown stones gain commercially attractive weight in a matter of months, while in nature this process takes centuries.

The term "synthetic" in relation to precious stones "from a test tube" is considered unfortunate in the jewelry environment, since consumers associate it with imitation and even fake. Jewelry with such stones, of course, has a more affordable price than with nuggets mined in mines and mines, but they cannot be called glass. By law, the manufacturer is required to indicate on the product label information that the stone is artificially grown. It is possible to distinguish synthesized stones from natural ones with the help of an examination in a gemological center, but not by sight.

Imitations are made of glass, minerals, metals, ceramics, plastic. They do not have a natural analogue, since they were “invented” in the laboratory. So, neither Swarovski crystals nor cubic zirconia have a similarity in nature, although they look like rock crystal and even diamonds. Imitating jewelry inserts are used in the manufacture of jewelry and accessories (watches), less often in jewelry.

Synthesized stones: a bit of history

The first synthetic stone - a 10-carat ruby - was obtained in 1891 by the French mineralogist Auguste Verneuil. Using the Verneuil method, it became possible to grow crystals suitable for jewelry use, and in 1910 synthetic sapphire was obtained in a similar way. Artificial emerald, identical to natural, was first grown in 1935.

But with the best friends of girls - diamonds - not everything is so simple. In 1954, the laboratory of the American company General Electric "ripened" the first artificial diamond, whose growth cycle could be repeated on an industrial scale. But it was a mineral of technical significance, not jewelry. Today, millions of carats of diamonds and diamond chips are produced annually in the world for the needs of manufacturers of various devices, devices, and tools.

Gem-quality artificial diamonds were developed by Herbert Strong and Robert Wentorf (both of General Electric) in 1970, but their counterparts have failed to fill the jewelry market today. The process of growing the king of stones is long, complicated and costly compared to other gems of laboratory origin. A diamond cut from a synthetic crystal can cost from 50% to 90% of the price of a natural nugget similar in weight and processing, or even exceed its cost. According to scientists, this direction is the future, but for now there is no need to fear that real diamonds in the jewelry business will be replaced by grown ones.

Imitation inserts: a bit of history

The most popular imitations of precious and semi-precious stones in jewelry are cubic zirconia and Swarovski crystals (rhinestones). Remember, cubic zirconia is not an artificial diamond! It does not contain the main element for diamonds - carbon, but there is zirconium oxide. Fianite was obtained in the mid-1960s by scientists from the P.I. Lebedev Physical Institute of the USSR Academy of Sciences (FIAN), after which it is named.

Georg Strass, a glassmaker and jeweler with German roots, who lived in French Alsace, invented in the 18th century to imitate diamonds using faceted lead glass. The surname of the master became the name of his invention: spectacular inserts were called "rhinestones". A century later, Strass's ideas were developed by Daniel Swarovski, a hereditary cutter of Bohemian crystal. He improved the composition of rhinestones, the quality of polishing and the durability of spraying, so that they were not inferior to diamonds with their beauty of cut, transparency, play of light and brilliance. In 1895, in Austria, Daniel founded the Swarovski company to sell his products to the whole world, and especially to the fashion designers of Paris. The business of a talented cutter, inventor of the first electric cutting machine (1892), thanks to the work of his descendants, is still flourishing. Swarovski crystals (rhinestones) have 12 facets, are made of high-quality crystal (glass with 32% lead oxide content) with the addition of powder of synthetic and natural stones of jewelry value.

Why do we need synthetic stones and imitations

First of all, "substitutes" for precious stones are good because they make jewelry more affordable. Buying a ring with artificially grown emerald without spending too much for your own budget or saving money for several months on the beauty created by nature is everyone's personal choice. And those who do not need to save up to purchase jewelry masterpieces prefer to wear inexpensive copies of jewelry outside of red carpets and gala dinners. Beyoncé, whose engagement ring with an 18-carat diamond is valued at $5 million, sets an example: for every day, the singer has a copy of this ring, which costs 1,000 times less - $5,000.

Also, the "alternative of luxury" fits into the global eco-trend - concern for the preservation of the environment, because the deposits of some precious stones are close to depletion these days.

And, finally, it is much easier to obtain ideal characteristics from a grown stone in terms of carat weight, color, light refraction, and the absence of any defects - inclusions, microcracks, and so on. There are laboratory centers for the production of synthetic stones in Russia, China, India, the USA, Sweden and other countries of the world.

Since people understood the nature of precious stones, learned their composition and revealed the conditions of formation, they have been striving to become like nature and reproduce stones with their own hands with the help of more and more new knowledge and technologies, and today they are successfully succeeding. Now people know how to make many types of jewelry and jewelry and semi-precious stones, which could not but affect the attitude towards minerals and prices, although the reason for the production of most stones is primarily the requirements of the industry, and only secondly - the demands of the jewelry market. However, passions around natural minerals and their artificially grown counterparts do not subside: there are lovers of natural stones who consider grown stones to be something fake, a kind of surrogate, and there are those who like any mineral, whether it is grown by man or nature.

In order not to get confused, you should immediately decide: there are imitations, but there are synthetic analogues of natural stones. Imitation- this is a material similar to natural stones in appearance and in some properties; imitations can be both artificially created minerals, and natural, natural, as well as materials that have nothing to do with minerals (glasses, plastics, etc.) or are combinations of all these materials. For example, natural colorless zircon, and artificially created cubic zirconia (which is often called zirconium in the trade), and simple glass, which does not even have a crystalline structure, can serve as imitations of a colorless diamond. If the seller passes off these materials as a diamond, they can be considered fakes. Synthetic analog- a mineral created by man, that is, artificially grown (for example, a synthetic diamond). Its characteristics correspond to the chemical composition, physical and optical properties of a diamond, and sometimes even surpass them, and its origin can only be established in a gemological laboratory, and with some stones it is difficult - they are so close to natural. In the "Gem Gallery" catalog you can see jewelry, in the descriptions of which the terms "synthesized ruby", "synthesized opal", etc. are used. - these are the grown stones.

Perhaps it cannot be attributed to one or the other category. improved materials- natural minerals, which have improved (in fact, changed) texture and / or color. This can be done by heating, X-ray irradiation, impregnation with resins, polymers, dyes, and the like. For example, reinforced turquoise is a natural, but very loose and soft turquoise, unsuitable in this form for jewelry inserts, which is strengthened by impregnation with special resins and sometimes dyes. It is clear that in this form, turquoise can no longer be considered completely natural, natural.

In our article, we will only talk about human-grown stones - we will look at some artificially created stones that are used for inserts in jewelry. Diamond

“I knew that it would take ten years, or even twenty, which could take away from a person all his strength, all his energy, but even then the game was worth the candle,” said the hero of H. G. Wells’ story “The Man Who Made Diamonds ". Usually, the synthesis of mineral crystals is associated with their demand in industry, in their application in high technology, but the stone itself attracts people, and the ability to repeat nature is even more so. diamond was one of the first such minerals. The first attempts to get diamonds were registered at the end of the 19th century, but they were unsuccessful. For the first time, artificial diamonds were synthesized in Sweden and the USA in 1954 (General Electric Company), and officially six years later - in the USSR. However, back in 1939, professor-physicist Ovsey Ilyich Leipunsky from the Institute of Chemical Physics described a method for obtaining diamonds, which involved the use of high pressures and temperatures of 1500-3000 degrees. Under these conditions, the loose crystal lattice of graphite can transform into a dense packing of the diamond structure. Such conditions were technically impossible at that time, but Leipunsky's work was studied by many specialists, including the Swedes; they later used the method described by O. I. Leipunsky: pressure, temperature, as well as the addition of iron and some other materials to graphite. This facilitates the synthesis process, carbon becomes mobile and forms a diamond lattice faster. The size of the crystals obtained at that time did not exceed only 0.8 mm, therefore they were used as abrasives. Large diamond crystals were synthesized later, this procedure is much more complicated and expensive. It is especially costly to synthesize large, more than one carat, and namely colorless diamond crystals, therefore their mass production is impossible, and there are mainly stones weighing one carat or less on the market.

One of the world's largest manufacturers of synthetic rough and polished diamonds, the Belarusian enterprise Adamas BSU (Adamas BSU), uses the BARS method (non-pressing apparatus "Cut Sphere") here. The basic technology based on this method was developed back in the USSR at the very beginning of the nineties; technology stands for "a method of crystallizing diamond from a carbon solution under conditions of a temperature gradient in a metal melt based on iron and nickel using high pressures." It will take about a hundred hours to synthesize a diamond weighing one carat in the BARS apparatus, which will be six cycles per month, that is, six carats. Unfortunately, only mass production of bright yellow crystals is possible. There are similar installations in Russia too, but they do not work for the jewelry market. Adamas BGU produces both technical raw materials and materials for the jewelry industry, and the share of the latter is steadily growing. This is due to a combination of reasons: a decrease in the production of natural diamonds, a constant increase in demand for diamonds, the decision of leading gemological laboratories, for example, the GIA (Gemological Institute of America) to accept synthetic diamonds for certification, the development of technology that makes it possible to obtain crystals of ever larger and more fancy colors while reducing the amount of "idle" synthesis. The market is gradually getting used to synthetic diamonds, and Belarus even adopted a special national program to develop the production of synthetic diamonds. However, there is no need to talk about cheap diamond jewelry yet. Corundum (sapphire, ruby)

Some of the most outstanding achievements of science and technology, as a rule, are marked by the use of mineral crystals, their unique properties: optical, piezoelectric, semiconductor and others. The very first corundums in Russia were also initially synthesized with the aim of applying them in science: in precision instrumentation, the watch industry, etc. In 1936, the first corundum growing plant in Russia was put into operation, and soon a permanent production was established. The first industrial method for obtaining corundum (as well as spinel) and still the most common is the Verneuil method.

The French chemist Auguste Verneuil began his experiments on growing minerals at the end of the 19th century, but 1905 is considered the official year of birth of the first synthetic corundums. The method, in brief, is as follows: alumina powder is fed along with oxygen into a burner fire, which in turn is fed with hydrogen. A hydrogen-oxygen flame at about 2050 degrees melts the powder, and the melt flows onto the prepared crystal carrier. Solidifying, the melt forms not a mineral crystal in the usual sense, but the so-called mineral boule - a rounded rod. Today it is possible to grow boules up to 5-8 cm in length and 2 cm in circumference (40-45 grams = 200-250 carats) in just a few hours. To get red corundum (ruby), chromium oxide is added to aluminum oxide powder; blue (sapphire) - add iron oxide and titanium. Nickel will color Corundum yellow. Star rubies and sapphires can also be grown. It has been produced in a similar way since the 1920s. spinel; for this, magnesium oxide and aluminum oxide are used. Spinels usually impart a sapphire blue, beautiful aquamarine or green coloration. "Gems Gallery" can bring to the attention of lovers of precious stones jewelry with high quality synthetic ruby and sapphire.

Every year, 200 tons of synthetic corundum and spinel are produced all over the world for various needs. Faceted, they are indistinguishable from natural gemstones without special equipment and are gaining more and more space under the sun. But can they finally replace natural rubies and sapphires? Alexandrite

Alexandrite is a variety of chryso beryl. This rare and very expensive stone belongs to the precious and has a unique effect: in daylight it is green, and in artificial light it turns red. The closest in properties imitation of Alexandrite and at the same time the most inexpensive is the same Corundum, only with the addition of vanadium and titanium during the synthesis process, which gives the stone an Alexandrite effect with an intense reverse from a faint bluish-greenish-gray to a rich red-violet, amethyst color. Actually synthetic Alexandrite is also grown; it is the most expensive synthetic analogue after a diamond. Information about the successful synthesis of an analogue of chryso-beryl-Alexandrite dates back to the second half of the 19th century.

In the USA, in 1964, an industrial method for obtaining alexandrite was tested, and since 1972, Creative Crystals (Saint-Ramon, Danville, California) has been growing alexandrite crystals using the flux method from solution. The solution of beryllium and aluminum oxides, cooling, serves as a "nutrient medium" for Alexandrite crystals, which grow from seven to nine weeks. In this way, the most beautiful Alexandrite crystals are obtained, which are difficult to distinguish from the famous Ural ones, which once made up the glory of Russian gems. The Japanese, on the other hand, produce Alexandrite by the Czochralski method (pulling a crystal from the melt) and call their product "inamori" and "cresent-vert": it also has the effect of a cat's eye, and its color changes from greenish-yellow in daylight to red-violet in artificial light. .

In Russia, Alexandrite has been grown since 1980 in Novosibirsk, at the Design and Technological Institute of Single Crystals. It goes both for technical and jewelry purposes; some crystals reach half a kilogram in weight. Although the synthetic analogue corresponds to natural Alexandrite both in chemical formula and in most properties, natural Alexandrite remains unsurpassed in beauty. It looks great in gold, as, for example, in turquoise earrings from the Gem Gallery collection.

Natural Alexandrite (like any other natural stone) has inclusions, cracks and other defects that are invisible to the eye, which do not reduce the aesthetic effect, but greatly interfere with the use of crystals in precision instrumentation, in particular, in Alexandrite lasers in medical cosmetology and eye microsurgery, therefore synthetic stones that do not have defects and have all the desired properties are ideal for this purpose. Emerald

Modern technologies make it possible to grow defect-free and fairly large Emerald crystals, which is very rare for natural crystals. By and large, grown Emeralds are no different from natural ones, except that they are too perfect. Synthetic Emeralds were obtained even before the Second World War, after which research in this area resumed with renewed vigor. The Americans from the Chatham company were among the first to establish the industrial synthesis of synthetic Emeralds from solutions in the melt. Of course, in the USSR it was also decided to create Emeralds, only by “our” method, according to new technology. Now this technology, created in the 1970s by Novosibirsk scientists, is known all over the world, and Emeralds created with its help are called Russian Emeralds. We are still ahead of the rest: the Tyrus company, which was founded in 1989 on the basis of the Joint Institute of Geology, Geophysics and Mineralogy of the Siberian Branch of the USSR Academy of Sciences by the same Siberian creators of Emeralds, is the market leader in artificial gems. Only in Tyrus and nowhere else in the world do they grow another variety of beryl besides the Emerald - aquamarines. For the synthesis of stones, a method is used that is closest to natural - hydrothermal, in an autoclave, using high pressures and temperatures. The process, by and large, is no different, and instead of thousands of years, only two or three months pass.

However, autoclaves, melts and high temperatures are not enough to grow stones; talent, intuition, and much more are needed, which can be called a gift to do this particular business. After all, if you choose the optimal composition of the charge (a mixture that will serve as a material for the growth of crystals) simply by experience, it will take all life, and even knowledge will not always help, rather, the totality of qualities that make a Creator out of a person. Pomegranate

Garnets are ideal crystals for use in lasers; they began to be grown in order to obtain defect-free samples of the desired properties. Almost by accident, they began to be used in the jewelry industry. In the 1960s, the first samples were obtained in the USA, and by the end of the sixties, synthetic Garnets entered the jewelry market. Unlike natural garnets, synthetic garnets can be colorless. This is another illustration of the issue of grown and natural stones, the perfection of the first and the imperfection of the second: the ideal pyrope in nature should have been colorless, but because of the “extra” iron impurities, it is the way we know it - fiery red, and not happens differently.

Synthetic Garnets (Garnetites) are yttrium-aluminum (YAG), gadolinium-gallium (GGG) and yttrium-ferruginous (IGG). Colorless and colored yttrium-aluminum garnets, which have a high hardness (8.5 on the Mohs scale) and a good refractive index, which give them brilliance and strong play, turned out to be the most suitable for inserts into jewelry, both in terms of physical and optical properties and economically. YAG is grown in various ways, mainly by the Czochralski method, which gives large crystals that lend themselves well to polishing.

Colorless Garnets sometimes replace diamonds. Even in London, which is notorious for its jewelry conservatism, synthetic garnets began to be sold in the early seventies as adequate substitutes for diamonds. This, in particular, was facilitated by the famous actress Elizabeth Taylor and the sensational story with her pear-shaped diamond. In 1969, Richard Burton (who starred with Taylor in Cleopatra and married her twice) presented her with a pear-shaped diamond weighing 69.42 carats. The actress usually wore this beautiful natural stone as a pendant, but the insurance for one evening cost a thousand dollars. Then Taylor ordered a copy of a diamond made of synthetic Garnet, similar in properties to a diamond, for three and a half thousand dollars. It was not difficult to distinguish the copy when it lay next to the diamond, but individually only an expert could do this. It just so happened that the fear of burglars, and perhaps insurers, contributed to the popularity of synthetic Garnets in general. In the Gem Gallery catalog there is a silver ring with fiery red synthetic Garnets that can outshine even small natural rubies. Quartz (rock crystal, amethyst, citrine, ametrine)

The production of Quartz in comparison with the same diamonds or Emeralds does not cause great difficulties. It is grown hydrothermally in steel autoclaves; the growth rate of crystals is up to 0.5 mm per day. Synthetic Quartz can be given any shade, both imitating natural and fantasy, not found in nature. For example, bright blue Quartz is obtained by adding cobalt; citrine color is provided by iron; the more it is, the brighter the color, to orange-red. Black morion can be grown by increasing the concentration of aluminum, and rauch topaz is also obtained - smoky Quartz. One of the most popular varieties of Quartz - amethyst - is obtained after ionizing irradiation of synthetic smoky Quartz. It is extremely difficult to distinguish from natural, so it is very popular. Synthetic amethyst is most often very bright and clean, without defects and heterogeneities, uniform deep color; stones can be very large, but sometimes their color changes in sunlight and artificial light, demonstrating a kind of alexandrite effect. amethyst brushes are grown in our suburbs, but as long as there is inexpensive African raw materials, there is no need for mass production of amethysts and amethyst brushes. ametrine (amethyst-citrine), a polychrome mineral with two color zones - purple and yellow - was first found in Bolivia, so its second name is bolivianite. But you can grow ametrine artificially; it will cost an order of magnitude lower, and will bring pleasure to the owner no less than natural, which, by the way, can be found in a faceted form in the collection of precious stones and crystals of the Gem Gallery. Opal

Synthetic opal, although with a stretch, can be called proper opal: it also has a layered structure, various colors and play of colors, for example, white opals with multi-colored flashes, cut in the form of pearls and adorned the ring from the Gem Gallery catalog. Like natural, synthesized opal also consists of silicon layers. For a very long time it was believed that opal could not be obtained artificially; the study of the structure of this amazing mineral nevertheless made it possible to understand that synthesis is possible. The first patent for the production of noble opal was received by Australian mineralogists A. Gaskin and P. Darre, and in 1973 the Swiss jewelry firm of Pierre Gilson began selling a wide variety of noble synthetic opals, which were in no way inferior in color and opalescence power to natural stones.

High-quality synthetic opals are also made in Russia. Even when comparing natural and artificial opal, it is difficult to understand which one appeared in the laboratory. In addition, natural noble opal is very expensive, especially black, and incredibly capricious in storage and wear, and grown stones allow you not to be afraid of any accidents. Turquoise

The mentioned company of Pierre Gilson in the mentioned 1972 also received artificial turquoise, the closest to natural of all previously obtained, and therefore suitable for inserting into jewelry. Such turquoise is very uniform, has a beautiful turquoise color, and cabochons made of such material are difficult to distinguish from natural ones even in a professional laboratory. All indicators (density, hardness, etc.) are the same, and even the best Iranian turquoise in the world is indistinguishable from artificial. In Russia, both uniform blue and gossamer turquoise are obtained, with a pattern of dark veins. You can try to compare natural turquoise beads and a gold ring with synthetic turquoise from the Gem Gallery collection to see how similar the materials are. Pearl

Pearl is in a special position among minerals: firstly, it is a mineral of organic origin, secondly, artificial, or cultivated. Pearl, in fact, differs from natural only in that it grows in a mollusk shell under human supervision. Back in the 19th century, the Chinese and Japanese began to cultivate Pearls, so it was in the East that a special attitude towards such Pearls developed and their own pearl traditions developed. The mollusks that are able to grow a pearl in their mantle are the martensi pinctada, the maxima pinctada, and the margaritifera pinctada, which grow up to thirty centimeters in diameter. This latter produces black, grey, bluish, green and bronze Pearls.

The method of obtaining Pearls is quite simple: the pearl shell is first grown in fresher water than sea water, in special fenced off areas to avoid attacks by predators; then, after three years, a ball of natural mother-of-pearl (or a piece of mantle) is placed inside the shells; further, pearl mussels grow from one and a half to eight years (on average, two to three years) in more salty water further from the coast. They are protected and cared for. Japanese Akoya cultured pearls are famous all over the world for their wonderful brilliance and various shades. This is a classic cultured pearl. Akoya pearls are produced not only in Japan, but also in Korea, China and Sri Lanka and can be white, yellow, pink, silver, champagne, green, cream.

You can diagnose cultured pearls with the help of ultraviolet rays: it will emit a greenish light, and natural - blue. "Gem Gallery" offers several shades of Pearls: white (classic beads of 45 cm, ideal for a round and oversized neck line), cream (earrings), gray (rings), the collections are constantly updated with new models with different colors.

It is interesting that in Russia there were attempts to grow pearls: the merchants Stroganovs in the 17th century set up experiments in Solvychegodsk, where a pond called Zhemchuzhny was preserved. Cheslav Khmelevsky grew pearls up to 5 mm in diameter in the east of Russia at the beginning of the 19th century. And the victory is awarded...

As it turns out, there are not so many synthetic analogues of jewelry stones; hardly twenty, but this is quite enough for the jewelry market, especially since there are many more imitations of stones, and they are also successfully sold, although the buyer is not always aware of this. And it’s much more pleasant to buy a ruby, albeit synthetic, than a “sandwich” made of glass, quartz and colored glue, and even more expensive. Natural stones, of course, will never lose their buyer; they are valuable because each of them is unique and has been growing for hundreds, millions of years. All impurities, defects, inclusions and heterogeneities only add to their individuality, which explains, in the end, their attractiveness and desire to admire them. But many of them, as a rule, are the most beautiful, difficult to obtain, and even more difficult to buy: the price for the love of beauty is too high. In this regard, we can be grateful to the grown stones: flawless, they invariably follow the same goal - to be even better, even more beautiful.

In the modern jewelry industry, various methods for the synthesis of precious stones and the cultivation of jewelry crystals have been successfully developed. All of them are tied to the phase state and composition of the medium. Very generally, we can say that crystals are grown from:

melts (pure substance)
solutions
gas environment

The synthesis process can proceed both as a result of the transformation of the initial solid phase, and by the formation of a solid phase from a liquid and a gaseous one. The most famous crystal synthesis methods are

melt (methods of Verneuil, Czochralski, zone and skull melting)
solution-melt (methods of flux, hydrothermal synthesis and synthesis of gem diamonds at high pressures)

Gemological Center Faculty of Geology of Moscow State University on its website gives a detailed description of the process and technologies for the synthesis of jewelry stones.

In general, we can say that the basis for obtaining synthetic jewelry crystals is the processes crystallization which, to one degree or another, we all studied at school in chemistry lessons. In fact, these are heterogeneous chemical reactions in which single crystals or their polycrystalline aggregates are formed.

The crystallization process consists of two key stages: first, the “center of the crystal” is born, then further growth occurs.

How does a gemstone crystal grow?

The crystal has a spatial lattice, which "overgrows" layer by layer with atoms of a supersaturated solution. The growth rate of the crystal is controlled by the medium temperature, pressure, and solution feed rate. If the growth rate is low, then the so-called "growth zoning" (similar to straight or curved lines) can form inside the crystal. In crystals with a saturated color, zoning can be color (that is, some faces will take on more impurities than others).

In addition, liquid and solid inclusions can “settle” on the crystal faces. The quality of the grown crystal often depends on the rate of its growth. Slow growth is more in line with nature's pace. With rapid stimulated growth, more inclusions remain on the faces, and the crystal may lose transparency.

Industrial Gem Gem Growth Methods

The era of industrial synthesis of precious and other jewelry stones was discovered in 1896 by a French scientist Auguste Verneuil. It was he who designed the first furnace with a burner based on oxygen and hydrogen, in which he received the first artificial ruby. Below in the table you can see a list of the most famous and used methods of growing stones. Stones of the same type, obtained by different methods, may have some differences.

It is important to note that in addition to growing single crystals, there are methods for synthesizing polycrystalline structures that make up such stones as turquoise and malachite. Their own, rather complex methods are also used to obtain a noble opal, which has a unique color effect (irisation). Most of these methods are trade secrets of the developers.

SYNTHESIS OF CRYSTALS FROM MELT
Verneuil method	Ruby, sapphire, star corundum, spinel, rutile
Czochralski method	Alexandrite, ruby, sapphire, spinel, YAG (yttrium aluminum granite) GGG (gadolinium gallium garnet)
Stepanov's method	Corundum (multicolored), leucosapphire, YAG
Bagdasarov's method (zone melting)	Rubies, leucosapphire, YAG
Garnissage method (cold crucible)	Sapphire, cubic zirconia
SYNTHESIS OF CRYSTALS FROM SOLUTIONS
flux method	Emerald, ruby, sapphire, spinel, alexandrite, YAG, YYY
hydrothermal method	Quartz and all its varieties, emerald, ruby
Synthesis from low-temperature aqueous solutions	Malachite, opal
SYNTHESIS OF CRYSTALS FROM THE GAS PHASE
Method of gas transport reactions	Chrysoberyl, phenakite

ALL STONES: CATALOG

JEWELERY STONES: DIRECTORY

SYNTHETIC JEWELERY STONES

Types of stones by origin (natural, imitation, synthesized, ennobled)

What determines the value of jewelry stones?

How to determine - synthetic jewelry stone or natural?

Imitation of natural stones and its methods

Refining precious stones

Zirconia, rhinestones, Swarovski crystals

Jewelry has always been loved and revered by both women and men. At all times, the presence of jewelry, their originality and value determined the position of a person in society, emphasized his status and wealth. This is explained by the high price of precious stones and jewelry, which only increases over the years. A grandson can sell great-grandmother's diamonds for fabulous money, provided that they are real, i.e. are of natural origin.

Most people in our country sincerely believe that precious (semi-precious) stones are set in all gold jewelry. This is the difference between real values and costume jewelry, the destiny of which is to shine with faceted glass. However, everything is not so clear. Already two centuries ago, scientists outwitted mother nature and learned how to create an imitation of precious stones - their synthetic counterparts.

"Glass" or "stone"?

The process of growing stones in laboratory and production conditions is quite complicated and time-consuming, therefore, such stones cannot be called glass, but, alas, they also do not have the right to bear the name "precious stones".

The history of the creation of artificial gems

The desire to obtain gold and precious stones from improvised materials has been inherent in mankind for a long time. Dreams of gratuitous wealth are reflected in fairy tales and legends, in which a person suddenly got the opportunity to turn any objects around him into gold. And despite the fact that such stories never ended with anything good, the thirst to catch up with nature in opportunities and get alchemical stones in the laboratory did not leave the mind and heart of scientists.

Not always successful attempts are honest: the history of artificial stones began in the eighteenth century, when the Austrian Georg Friedrich Strass found a way to sell glass under the guise of noble diamonds. On the banks of the river Rhine, Strass discovered pieces of minerals that, in certain light, looked like diamonds. By processing, cutting and introducing lead salts into glass, artificial stones were obtained, very similar to real ones, which were sold by a skilled businessman as precious. In order for the “jewels” to shine more strongly, the thinnest metal spraying was applied to their surface. The great strategist not only was not punished for selling fake stones, but, on the contrary, he was granted the title of jeweler in the king's palace, and glass jewelry was named after him - rhinestones.

Today, the most famous in the world are rhinestones, bearing the name "Swarovski Crystals". It is very symbolic that they are made in the homeland of Strass - in Austria. The main materials for the manufacture of Swarovski Crystals are crystal, synthetic and precious stones of natural origin, so they have a fairly high cost.

As for stones, the first stone grown by man, like an exotic flower, was revealed to the public back in 1891. Prior to this, repeated attempts were made to grow stones. However, the results were of such microscopic dimensions that there was no need to talk about their use in industry (for example, in jewelry). The "Siamese" stones, which were obtained by alloying fragments of stones of natural origin, were not successful either.

The artificial ruby, obtained in the laboratory, reached ten carats, and was created by the Frenchman Auguste Verneuil. All the equipment for obtaining stones was invented by him and made it possible to obtain pure synthetic rubies in a few hours two to three times more than the received sample. At the same time, unlike natural stones, they did not have inclusions and defects, they were clean and transparent. A year later, the same scientist obtained the first corundum of synthetic origin. The raw material for it was purified aluminum oxide.

Ten years after the first success, the research was completed and the equipment for growing synthetic stones was successfully introduced into production. The Verneuil method turned out to be simple and reliable, it allowed growing rubies of the required size and prompted scientists to create other synthetic stones.

The twentieth century picked up the baton, and additional methods were discovered for growing stones “in test tubes”. Their assortment expanded, and such stones became very popular with jewelers, because at a lower cost it was possible to get a larger stone and purity unprecedented for natural gems.

In the Soviet Union in the middle of the last century, synthetic stones were in great demand, they can be found in many jewelry of that era: bright red, glowing rubies and blue transparent sapphires, grown using the method proposed by the French scientist. In addition to them, other synthetic stones are known: alexandrite, emerald, quartz and diamond. And the phianite, which is often found and loved by ladies, imitating a diamond, has no analogues in nature at all - it is 100% the merit of scientists.

How to distinguish a gem

An ordinary layman, neither at first glance, nor at a second, or even at a third glance, will be able to recognize which stone is set in the frame - synthetic or precious (precious, after all, stones of purely natural origin are called precious). In the EU countries and in the USA, the rights of buyers are very strictly observed, and the product tag must contain information about the origin of the stone. If the stone was inherited and there is no information about it, except for family legends, then you should contact a serious jewelry workshop or laboratory for a comprehensive analysis. With the help of special equipment, specialists will be able to answer your question. But even if the stone is not natural, but synthetic - do not rush to get upset, it still cannot be considered glass, suitable only for cheap jewelry. Synthetic stones make it possible to reduce the cost of products, they allow more economical use of minerals - diamonds, deposits of precious stones and, who knows, maybe after some fifty or a hundred years, our descendants will seriously attend to the preservation of nature, ecology, earth's interior, and synthetic stones will be at a huge price and in trend.

Popular in category: