What is the hardest mineral in the world. The strongest stone in the world. Astrology about diamonds

The hardness of stones is determined by Mohs scratch hardness and Rosival hardness. Nowadays, only collectors and amateurs determine the hardness of stones using the Mohs scale. Previously, when optics was not yet highly developed, the authenticity of precious stones was determined by the method of determining scratch hardness. Now they have learned to grow stones artificially and therefore the Mohs method does not determine very accurately. This method of determining hardness was invented by the Viennese mineralogist Friedrich Mohs. This method has the disadvantage of damaging the stone, but it also has advantages; it does not require expensive equipment or a laboratory.
The principle of this method is to determine the resistance of a stone to scratching its surface with a sharp special object. Stones with a Mohs hardness above 7 are hard stones, and stones with a Mohs hardness below 7 are susceptible to abrasion by ordinary dust, since the dust contains tiny grains of quartz that have a Mohs hardness of 7. Therefore, stones with a Mohs hardness below 7 quickly become dull and wear off quickly. polished and are severely scratched when in contact with harder objects. It is necessary to measure scratch hardness only with the sharp edge of a sample only on smooth and fresh surfaces of the stone, and if you determine it on ribbed formations or on ores weathered from the surface, then the scratch hardness values ​​will be underestimated. Some stones on different faces and on different planes may have different scratch hardness. For example, diamond has such differences and thanks to this it can be polished, although the hardness of diamond on the Mohs scale is considered the highest.
Below is a relative Mohs hardness scale for stones that shows how a stone can be scratched and what Rosival grinding hardness a stone has depending on its Mohs scratching hardness.

Mohs scale table for simple determination of hardness

Having determined the scratching hardness of the stone, you can then use a specially created table to determine the suitability of the stone.
Mohs relative table.

The precious stone some time ago lost its title of the hardest material in the world, giving way to artificial nanomaterials of slightly greater hardness. Today, a rare natural substance looks set to leave all others behind - it is 58% harder than diamond.

Zicheng Pan from Shanghai Jiao Tong University and his colleagues modeled how atoms in two substances supposedly having the properties of very hard materials would respond to a special sensor.

Extreme conditions

The first is wurtzite boron nitride, which has a structure similar to diamond, but consists of different atoms.

The second is the mineral lonsdaleite, or hexagonal diamond, made up of carbon atoms like diamond, but they are organized differently.
Modeling showed that wurtzite boron nitride can withstand 18% more impact than diamond, and lonsdaleite - 58% more. If the results are confirmed by physical experiments, both materials will be much harder than any known substance.

But it will not be easy to carry out such tests, because both materials are not often found in nature.

The rare substance lonsdaleite is formed when meteorites containing graphite fall to Earth, while wurtzite boron nitride is formed during volcanic eruptions under high temperatures and pressure.

Flexibility

If successful, wurtzite boron nitride may become the more useful of the two due to its resistance to oxygen at higher temperatures than diamond. This makes it ideal for use on the ends of cutting and drilling tools operating at very high temperatures, or as corrosion-resistant films on the surfaces of spacecraft, for example.

Paradoxically, wurtzite boron nitride owes its hardness to the flexibility of the bonds between the atoms that form it. When the material is stressed, some bonds change direction by almost 90º to relieve stress. After diamond and wurtzite boron nitride were subjected to the same process, something in the structure of wurtzite boron nitride made it nearly 80% harder, says study co-author Changfeng Chen of the University of Nevada, Las Vegas.

Scientists emphasize that in order to prove the theory, single crystals of each material are needed. There is currently no way to isolate or grow such crystals.

Today there is no unified classification of semi-precious stones, there is only a conditional division. You can find out everything about the stones and their description properties on the website http://www.catalogmineralov.ru/cont/poludragocennye_kamni.htm. When deciding to give a gift with a semi-precious stone to a loved one, first get to know the stone.

If you are interested in building stone, then they are divided into five classes.

Very strong, strong, medium strength, soft and very soft. These are all natural materials.

Sturdy and very strong. (strength over 100 MPa) these are quartzites, granites, porphyries, basalts, marble-like and dense limestones. To answer your question, quartzites and granites are the strongest.

Medium strength(tensile strength 60-80 MPa) these are siliceous shales, limestones and sandstones affected by weathering.

Soft class(Strength limit 30-40 MPa) these are porous limestones, calcareous dolomites, ferruginous, thin-film sandstones.

Very soft class-weathered igneous rocks, powdery, earthy limestones, weak sandstones, shales.

User is unlocked

Even more than a plus. Plus with a plus. - 4 years ago

9 months ago

Diamond. This is also a stone, only precious. In general, it is correct to call it a mineral. It has the highest strength on the Mohs scale. If you take a diamond and run it across almost any surface, there will be a scratch on it. Even if you use a stainless steel knife, you will still scratch it, just like glass.

However, it can easily break, as it is fragile. In this regard, strength is a very relative thing.

The hardest mineral in nature

November 4, 2016

It originates in the depths of red star giants, is part of vital fats, amino acids and carbohydrates, can form millions of compounds with different chemical elements and, depending on its structure, has completely different mechanical properties. The soft and brittle pencil core and the hardest mineral, diamond, are made of the same building material - carbon. What makes a diamond so unique? Where is it used? What is its value?

Indestructible Thermal Conductor

Translated from ancient Greek, the word “diamond” means “indestructible.” Even before antiquity, people knew the incredible strength of this stone. In ancient times, diamonds were widely traded in India and Egypt. And this mineral came to the European expanses after the aggressive campaigns of Alexander the Great. He brought the stones as magical artifacts. The ancient Greeks called this hardest mineral the tears of the gods that fell to the ground.

But the secret of the stone’s indestructibility lies, of course, not in mysticism or in connection with the spiritual world. The clear lattice structure of the element in the form of tetrahedrons and the strong bond between carbon atoms provide the highest strength. Thanks to this same structure, diamond is an excellent thermal conductor. For example, if it were possible to make a teaspoon from a single piece of diamond, you would not be able to stir sugar in hot tea with it, because you would get burned the moment the spoon touched the boiling water.

Comparison of mineral hardness

How to determine which mineral is the hardest? The talented German mineralogist Karl Friedrich Moos took up this issue in earnest in the nineteenth century. In 1811, the scientist proposed using a comparative scale to determine the hardness of various minerals. It consists of ten points, each of which corresponds to a specific mineral. The first (talc) is the softest, and the last, accordingly, the hardest. Verification is carried out experimentally. If a sample (for example, silver) is scratched by fluorite, which is number four on the scale, but is not damaged by gypsum (scale standard number two), then the silver has a hardness of 3 on the Mohs scale.

The hardest mineral is diamond. He ranks tenth. And although the Mohs table was introduced in the early nineteenth century, it still remains widely applicable. However, it is worth remembering that this table is not linear. This means that a diamond ranked tenth will not be exactly twice as hard as apatite, which ranks fifth in the table. Other methods are used to determine the absolute value of hardness.

From kings to workers

For a long time, diamonds were the exclusive prerogative of jewelry makers. However, with the development of industry, this hardest mineral increasingly began to be considered not only from the usual aesthetic side, but also from the point of view of its unique physical properties. At first, natural diamonds that could not be cut were used in the production of instruments. These are stones that had defects that could not be corrected by a jeweler. They began to be called industrial diamonds.

As time passed, the need for tools with diamond cutting and drilling edges increased. For example, diamond drills are in great demand in the construction industry. Their advantage over their counterparts made from hard metal alloys is that when working with a diamond drill, microcracks do not form in the material. Diamond easily and cleanly cuts any material, be it stone, concrete or metal. And the absence of microcracks is the key to the durability of the structure. In addition, the work process itself is much faster, noticeably easier and much quieter.

Based on this, it is not surprising that, according to data for 2016, in Russia alone, 1,200 types of various tools and equipment are produced, the main working part of which is diamond.

Application in medicine

The hardest mineral in nature is not only suitable for use in processing rough and hard rocks. Diamond is also indispensable in medical instruments. After all, the thinner and more accurate the tissue incision, the better the body copes with recovery. And for complex operations on vital organs, the width of the incision plays a decisive role even more so.

In addition, a scalpel with a thin diamond film on the blade remains sharp for a long period of time.

Prospects in electronics

The development of diamond integrated circuits is also actively progressing. They use tiny diamonds for the backing. Equipment produced using this method is more resistant to temperature changes and large voltage surges. Diamonds can also be used to transmit data in telecommunications. The features of these crystals allow signals of different frequencies to be transmitted simultaneously over the same cable.

The hardest mineral on Earth helps in space exploration

Diamond is also in demand in the chemical industry. An aggressive environment that easily damages glass is absolutely not dangerous for diamond. Physicists use crystals to conduct quantum physics experiments and explore outer space.

When creating telescope optics, the requirements for accuracy and reliability of materials become critical. This is where the hardest natural mineral, which has outstanding physical and chemical parameters, comes into play.

Diamond synthesis

With such an intense demand for the hardest precious mineral, the question of its artificial synthesis became acute. Let us note that no reserves of stones are able to satisfy the ever-increasing demand. And after lengthy experiments, scientists managed to create an analogue of natural diamond that has all the necessary features. Today, the production of artificial diamonds for industrial needs has already become common practice.

There are several methods for synthesizing this mineral. The first is the closest to its formation in the natural environment. Synthesis is carried out using ultra-high temperature and enormous pressure. The second technique allows you to extract diamond from steam. It is used in film technology - crystals are applied in a thin film to the cutting edges of tools. This method is especially in demand in the manufacture of surgical instruments. And the third produces a scattering of small crystals using detonation and rapid cooling.

Experiments continued and boron nitride was synthesized, which is 20% harder than natural diamond. However, so far this substance is so small that diamond traditionally continues to be considered the hardest mineral.

10 new mysteries that prove that Earth is a mystical place! Every year is a crazy period of time for one reason or another, and no one will deny it. Here are 10 secrets that prove that our...

20 photos of cats taken at the right moment Cats are amazing creatures, and perhaps everyone knows about this. They are also incredibly photogenic and always know how to be in the right place at the right time.

13 signs that you have the best husband Husbands are truly great people. What a pity that good spouses don't grow on trees. If your significant other does these 13 things, then you can s.

11 Weird Signs That You're Good in Bed Do you also want to believe that you please your romantic partner in bed? At least you don't want to blush and apologize.

Surprise: Husbands Want Their Wives to Do These 17 Things More Often If you want your relationship to be happier, you should do the things on this simple list more often.

How to look younger: the best haircuts for those over 30, 40, 50, 60 Girls in their 20s don’t worry about the shape and length of their hair. It seems that youth is created for experiments with appearance and daring curls. However, already last.

Diamond is no longer the hardest natural material in the world

Diamonds will forever remain the girls' best friends, but soon they risk losing their favor in the industrial sphere.

The precious stone some time ago lost its title of the hardest material in the world, giving way to artificial nanomaterials of slightly greater hardness. Today, a rare natural substance looks set to leave all others behind - it is 58% harder than diamond.

Zicheng Pan from Shanghai Jiao Tong University and his colleagues modeled how atoms in two substances supposedly having the properties of very hard materials would respond to a special sensor.

The first is wurtzite boron nitride, which has a structure similar to diamond, but consists of different atoms.

The second is the mineral lonsdaleite, or hexagonal diamond, made up of carbon atoms like diamond, but they are organized differently.
Modeling showed that wurtzite boron nitride can withstand 18% more impact than diamond, and lonsdaleite - 58% more. If the results are confirmed by physical experiments, both materials will be much harder than any known substance.

But it will not be easy to carry out such tests, because both materials are not often found in nature.

The rare substance lonsdaleite is formed when meteorites containing graphite fall to Earth, while wurtzite boron nitride is formed during volcanic eruptions under high temperatures and pressure.

If successful, wurtzite boron nitride may become the more useful of the two due to its resistance to oxygen at higher temperatures than diamond. This makes it ideal for use on the ends of cutting and drilling tools operating at very high temperatures, or as corrosion-resistant films on the surfaces of spacecraft, for example.

Paradoxically, wurtzite boron nitride owes its hardness to the flexibility of the bonds between the atoms that form it. When a material is stressed, some bonds change direction by almost . After diamond and wurtzite boron nitride were subjected to the same process, something in the structure of wurtzite boron nitride made it nearly 80% harder, says study co-author Changfeng Chen of the University of Nevada, Las Vegas.

Scientists emphasize that in order to prove the theory, single crystals of each material are needed. There is currently no way to isolate or grow such crystals.

Today there is no unified classification of semi-precious stones. there is only a conditional division. You can find out everything about the stones and their description properties on the website http://www.catalogmineralov.ru/cont/poludragocennye_kamni.htm. When deciding to give a gift with a semi-precious stone to a loved one, first get to know the stone.

The hardest materials on Earth TOP 10

Each of you knows that diamond remains the standard of hardness today. When determining the mechanical hardness of materials existing on earth, the hardness of diamond is taken as a standard: when measured by the Mohs method - in the form of a surface sample, by the Vickers or Rockwell methods - as an indenter (as a harder body when studying a body with less hardness). Today, there are several materials whose hardness approaches the characteristics of diamond.

In this case, original materials are compared based on their microhardness according to the Vickers method, when the material is considered superhard at values ​​of more than 40 GPa. The hardness of materials can vary depending on the characteristics of the sample synthesis or the direction of the load applied to it.

Fluctuations in hardness values ​​from 70 to 150 GPa are a generally established concept for solid materials, although 115 GPa is considered to be the reference value. Let's look at the 10 hardest materials, other than diamond, that exist in nature.

10. Boron suboxide (B 6 O) - hardness up to 45 GPa

Boron suboxide has the ability to create grains shaped like icosahedrons. The formed grains are not isolated crystals or varieties of quasicrystals, but are peculiar twin crystals, consisting of two dozen paired tetrahedral crystals.

10. Rhenium diboride (ReB 2) - hardness 48 GPa

Many researchers question whether this material can be classified as a superhard type of material. This is caused by the very unusual mechanical properties of the joint.

The layer-by-layer alternation of different atoms makes this material anisotropic. Therefore, hardness measurements are different in the presence of different types of crystallographic planes. Thus, tests of rhenium diboride at low loads provide a hardness of 48 GPa, and with increasing load the hardness becomes much lower and is approximately 22 GPa.

8. Magnesium aluminum boride (AlMgB 14) - hardness up to 51 GPa

The composition is a mixture of aluminum, magnesium, boron with low sliding friction, as well as high hardness. These qualities could be a boon for the production of modern machines and mechanisms that operate without lubrication. But using the material in this variation is still considered prohibitively expensive.

AlMgB14 - special thin films created using pulsed laser deposition, have the ability to have a microhardness of up to 51 GPa.

7. Boron-carbon-silicon - hardness up to 70 GPa

The basis of such a compound provides the alloy with qualities that imply optimal resistance to negative chemical influences and high temperatures. This material is provided with a microhardness of up to 70 GPa.

6. Boron carbide B 4 C (B 12 C 3) - hardness up to 72 GPa

Another material is boron carbide. The substance began to be used quite actively in various fields of industry almost immediately after its invention in the 18th century.

The microhardness of the material reaches 49 GPa, but it has been proven that this figure can be increased by adding argon ions to the structure of the crystal lattice - up to 72 GPa.

5. Carbon-boron nitride - hardness up to 76 GPa

Researchers and scientists from all over the world have long been trying to synthesize complex superhard materials, with tangible results already achieved. The components of the compound are boron, carbon and nitrogen atoms - similar in size. The qualitative hardness of the material reaches 76 GPa.

4. Nanostructured cubonite - hardness up to 108 GPa

The material is also called kingsongite, borazon or elbor, and also has unique qualities that are successfully used in modern industry. With cubonite hardness values ​​of 80-90 GPa, close to the diamond standard, the force of the Hall-Petch law can cause their significant increase.

This means that as the size of the crystalline grains decreases, the hardness of the material increases - there are certain possibilities for increasing it up to 108 GPa.

3. Wurtzite boron nitride - hardness up to 114 GPa

The wurtzite crystal structure provides high hardness to this material. With local structural modifications, during the application of a particular type of load, the bonds between atoms in the lattice of the substance are redistributed. At this moment, the quality hardness of the material increases by 78%.

2. Lonsdaleite - hardness up to 152 GPa

Lonsdaleite is an allotropic modification of carbon and has a clear similarity to diamond. A solid natural material was discovered in a meteorite crater, formed from graphite, one of the components of the meteorite, but it did not have a record degree of strength.

Scientists proved back in 2009 that the absence of impurities can provide hardness exceeding the hardness of diamond. High hardness values ​​can be achieved in this case, as in the case of wurtzite boron nitride.

1. Fullerite - hardness up to 310 GPa

Polymerized fullerite is considered in our time to be the hardest material known to science. This is a structured molecular crystal, the nodes of which consist of whole molecules rather than individual atoms.

Fullerite has a hardness of up to 310 GPa, and it can scratch a diamond surface like regular plastic. As you can see, diamond is no longer the hardest natural material in the world; harder compounds are available to science.

So far, these are the hardest materials on Earth known to science. It is quite possible that new discoveries and breakthroughs in the field of chemistry/physics will soon await us, which will allow us to achieve higher hardness.

The most expensive gems in the world. Top 19 (with photos)

Many people mistakenly believe that the limit of the high cost of precious stones stops at diamonds, but in nature there are other, no less beautiful, but rarer minerals, the price of which often exceeds the cost of diamonds.
Below we present to your attention a rating of the most expensive precious stones in the world. A high price is usually determined by a unique combination of rarity, beauty and high demand. The list shows the average cost of high quality stones available on the world market today, however it should be noted that some prices are approximate, as particularly valuable gems are often sold privately, without disclosure to the general public.

19th place: Eremeevit- a rare gemstone, first discovered in 1883 in the southeastern part of the Trans-Baikal Territory. At first it was mistaken for aquamarine, since the first crystals found were light blue. Over the last century, light yellow and even colorless examples have been discovered, but blue ones are still the most expensive on the gem market. The gem received its name in honor of the Russian mineralogist Pavel Eremeev. It is reliably known that at the moment there are several hundred faceted eremeyevites, the cost of which averages $1,500 per carat.

18th place: Blue Garnet- the rarest representative of a number of these minerals, which was first discovered in Madagascar only in the late 1990s. Today, stones of this color are found in Tanzania, Sri Lanka, Kenya, Norway and the USA. Their main distinguishing feature is the ability to change their shade when the lighting changes. So in daylight they acquire blue, indigo and green tints, and in artificial light they become purple or red. Today, the average cost of this high-quality gemstone is 1,500 USD. per carat

17th place: Black opal- the most valuable of the group of opals, the bulk of which is mined in the vastness of Australia. Other rich deposits are Brazil, USA, Mexico. The color of opals of this type can vary from grayish to black with a rich variety of shimmering tints of all colors of the rainbow. Although today these precious stones are no longer considered as rare as they used to be, they are nevertheless quite expensive. The cost of high quality black opal is approximately $2,000 per carat.

16th place: Demantoid- a gemstone from the group of garnets of green or yellowish-green color, for a long time known only in collectors' circles. The main deposits of these gems are located in Iran, Pakistan, Russia, Kenya, Namibia and Tanzania. Every year the popularity of the mineral is steadily increasing, along with which comes an increase in its value. Currently, a carat of top-class demantoid can be purchased on the world gemstone market for $2,000.

15th place: Taaffeit- one of the rarest gems in the world, named after its discoverer, Count Eduard Taaffe, who in 1945 accidentally discovered an unusual specimen in a purchased batch of cut gems that he had never seen before. The range of shades of taaffeite can vary from lavender to pale pink. Today, the unique mineral is found in small quantities only in some placer deposits in Sri Lanka and southern Tanzania. The cost of high-quality specimens of taaffeite varies between 2-5 thousand dollars.

14th place: Poudretteite / Poudretteite is a rare pink mineral first discovered in 1987 in Quebec (Canada). It got its name in honor of the Poudrette family, which still owns the same mine in Mont Saint-Hilaire where the first sample was found. Quality stones only began to appear in 2000, when several specimens were found in northern Mogog (Myanmar). Since 2005, the mineral has not been discovered there, and the Canadian deposit has given the world only about 300 stones of varying quality. Depending on the color saturation and purity, the cost of poudretteite can range from 3 to 5 thousand conventional units.

13th place: Musgravit- a close relative of taaffeite, to which it is similar in appearance and chemical composition. It was first discovered in 1967 in Australia's Musgrave Range. Later, the mineral was found in Greenland, Tanzania, Madagascar and even in the depths of the cold lands of Antarctica. This gem comes in several colors, but the most common are green and purple. Due to the fact that very small quantities of these precious stones have been found throughout history, their price reaches quite expected levels: the cost of a carat of high-quality green musgravite is 2-3 thousand dollars, while for one carat of a purple faceted mineral you will have to pay about 6 thousand conventional units.

12th place: Benitoite- a deep blue gemstone, the only deposit of which is located in San Benito County, (California, USA), where it was first discovered back in 1907. In 1984, it was officially designated as the State Gemstone of the state. On the world market, the average cost of small benitoite weighing 1 carat, of which there is an extremely limited quantity in the world (no more than a dozen), is 4000-6000 USD.

11th place: Sapphire- one of the most famous jewelry stones, in mineralogy and the jewelry industry called corundum. It has a deep blue color; pink, green and yellowish-orange gems are less common. The rarest varieties include blue star sapphire and padparadscha, an orange and red-yellow colored stone. The most famous deposits of these minerals are located in India, Russia, Vietnam, Thailand, USA, Australia, Myanmar, Sri Lanka, China and Madagascar. The rarest and highest quality specimens on the world market can be purchased for approximately 4-6 thousand conventional units per carat.

10th place: Emerald- a gemstone of the highest quality, bright green or dark green. In recent years, Colombia has been named the main deposit of this mineral. Despite the large number of emeralds actively mined all over the world, their prices still remain truly astronomical. Today, pure stones are extremely rare, which, together with their enormous popularity, determines their high cost. A green gem of exceptional quality weighing approximately 1 carat sells for more than $8,000 on the world market.

9th place: Bixbit- a rare variety of red beryl, until recently known only to some collectors. It is mined exclusively in the American states of Utah (Waho-Waho Mountains) and New Mexico. It is extremely difficult to purchase high-quality red beryl, and the price for a stone weighing about 1 carat is more than 10-12 thousand US dollars. Determining the average cost of this mineral is quite difficult due to the small number of high-quality stones offered for sale.

8th place: Alexandrite is a famous gemstone famous for its ability to change color. In daylight, its color is characterized by bluish-green, dark blue-green and olive green, while in artificial light its iridescence can take on pink-crimson, red, purple or violet-red. The first crystal was discovered in 1833 at an emerald mine in the vicinity of Yekaterinburg. The cost of this precious stone, depending on its quality, can range from 10 to 15 thousand conventional units.

7th place: Paraiba (blue tourmaline)- a beautiful and very rare crystal of bright blue-turquoise color, discovered in 1987 in the state of Paraiba, in eastern Brazil. For a long time, this gemstone was mined in only one place, but today there are already deposits of it in Madagascar and Mozambique. Brazilian blue tourmalines are by far the most expensive representatives of the group - their price is 12-15 thousand dollars per carat, and a truly unique gem of the highest quality can far exceed these figures.

6th place: Ruby is one of the most popular gemstones in the world, known for its rich shades of red: bright red, violet-red, dark red. It is found, like diamonds, on all continents, excluding Antarctica. The main exporting countries are Thailand, Myanmar and Sri Lanka. The most valuable are Asian rubies, especially stones of the “pigeon’s blood” color - pure red with a purple tint. Their limited quantity and enormous popularity make them extremely expensive gemstones. For a carat of high quality ruby ​​on the world market you will have to pay about 15 thousand dollars.

5th place: Diamond is a common mineral that has long remained one of the most expensive and desirable gemstones. The reason for this, of course, is the enormous popularity of diamonds (as cut diamonds are called). Every year the number of manufactured jewelry with these precious stones is rapidly increasing. Industrial diamond deposits are now known on all continents except Antarctica. Currently, a perfectly cut D color diamond sells on average for about 15,000 USD. e. per carat.

4th place: Jadeite (imperial) is a green mineral that has long held the status of one of the most mysterious stones on our planet. Today, its main sources are in China, Upper Myanmar, Japan, Mexico, Kazakhstan, Guatemala and the USA. The approximate cost of a carat of high quality jadeite on the world market is 20 thousand dollars.

3rd place: Padparadscha(translated from "sunrise color" in Tamil) are pinkish-orange sapphires that were historically mined in Sri Lanka, Tanzania and Madakascar. Nowadays in Sri Lanka there is practically no padparadscha left in its natural form and it is obtained by heating the corundum mineral in a furnace to the desired condition. The last classic (i.e. unheated) padparadscha weighing 1.65 carats was sold in Sri Lanka about 20 years ago for $18,000. Now padparadscha weighing over five carats is considered collectible and can be valued at up to 30 thousand dollars for each carat of weight.

2nd place: Grandidierite is a rare greenish-blue, greenish-blue or bluish-green mineral, the first specimen of which was discovered in Sri Lanka. At the beginning of the twentieth century, it was described by the French explorer Alfred Grandidier, who was engaged in the study of Madagascar, on the territory of which the bulk of these minerals are still mined today. Faceted grandidierites today exist in extremely limited quantities - about two dozen. The approximate cost of the unique mineral is more than 30 thousand dollars per carat.

1st place: Red Diamond- the most expensive member of its family and also the most expensive gem in the world. In the entire history of mankind, only a few specimens of this mineral have been found and most of them have a very small weight - less than 0.5 carats. The color of a natural red diamond is called purple-red by gemologists. The only deposit of colored diamonds is located in the Argyle diamond mine (Australia), where only a few stones are mined annually. Gemstones weighing more than 0.1 carats typically only appear at auctions where the price per carat is more than one million dollars.

GEMS

DIAMOND

Diamond- a type of crystalline carbon, hardness -10 on the Mohs scale (the hardest stone); Due to the peculiarities of the internal structure of the stone, a strong splitting of light occurs inside the stone, providing an unsurpassed “game” (irization). The best cut option is the classic diamond cut (KR-57).
A diamond is a cut diamond. Diamonds have been known to people for about five thousand years. The Arabs called it “almas” - the hardest. The Greeks gave him the name “adamas”, which translated means irresistible, indestructible.

Diamond is the most valuable among all jewelry stones. Not a single gem can compare with it in the brightness of its shine and the play of all the colors of the rainbow. Moreover, this property is preserved even if the ring or earrings with diamonds have not been cleaned for a long time. The high price is explained by the rarity and exceptional complexity of the cut. According to an old belief, cutting should not be abandoned for a long time and the work should not be passed on to each other, as the quality will be much worse.
Completely colorless (pure water) or slightly bluish varieties are highly valued. Unfortunately, most diamonds have faint yellowish, brownish and other colors that reduce their value. There are blue, pink, red, green, yellow, orange, blue and black diamonds.

The largest diamond found is the Cullinan, the Orlov diamond with a greenish-blue tint crowns the royal scepter of Russia. The magnificent Hope Diamond weighs only 45.5 carats and has a rare sapphire blue color. Today it is the most expensive small object in the world, each carat is worth about $5 million!

In 2000, a unique organization was created - the Kimberley Process, the goal of which is to fight for the “purity” of the origin of diamonds. Each participating country that mines and purchases them can only trade if they have a Kimberley certificate confirming the legal origin of the stones.
A common misconception is that cubic zirconia (cubic zirconia) is an artificial diamond. However, this is not true; cubic zirconia is an artificial crystal, most often used as a diamond substitute. And the technology for creating artificial diamonds is so complex that the jewelry obtained in this way will be three times more expensive than a natural one.

RUBY

Ruby- a transparent variety of corundum, and thanks to the admixture of chromium, the stone sparkles with a deep red color. Hardness on the Mohs scale is 9 points. The palette of the gem is very diverse, ranging from light pink to deep red. There are rubies that combine blue and red colors, which gives a lilac or violet color. Sometimes the stone contains inclusions of the mineral rutile, which gives it a silky, pearlescent sheen and an asterism effect.

Ruby is one of the four most expensive jewelry stones. In terms of hardness, it is second only to diamond, and star-shaped crystals are valued more than diamonds. Such varieties are amazingly beautiful - in the center there is a bright sparkling point, from which six flickering rays radiate across the surface. Among rubies, the shade of piercing red with a violet tint, called “pigeon’s blood,” also stands out for its charm and value. Traditionally, the most valuable stones are deep red, with a slight purple tint.

Large crystals are found in nature much less frequently than similar diamonds: the largest known jewelry ruby ​​weighed 400 carats, three stones were cut from it. The cost of natural ruby ​​is very high, and not everyone can afford it. But a synthetic crystal is available to many admirers of beautiful stones, thanks to the French chemist A.E. Alexander, who created an artificial ruby ​​in his laboratory in 1910.

In an ancient Indian treatise, two thousand years before the birth of Christ, he is called the “king of precious stones.” In Burma, where the best rubies in the world have been mined since ancient times, they believe that it brings invulnerability, but for this it had to be worn without taking it off, so that it becomes, as it were, part of the owner’s body, after which the owner can not be afraid of either a spear, or a sword, or arrows. The Burmese firmly believe that the national hero of Burma, Aung San, who never parted with a ruby, was killed by terrorists, having for the first time forgotten his amulet in the bathroom that day.
The largest known ruby, the Raja Ratna, weighs almost half a kilogram (2475 carats) and belongs to a modest Indian lawyer who inherited it.
In the old days, almost all red gems were called rubies, and many famous ones turned out to be noble spinels, garnets, and tourmalines. Thus, a red stone the size of a pigeon egg (250 carats), which the Swedish king Gustav Adolf III presented to Empress Catherine II as a ruby, turned out to be pink tourmaline.

SAPPHIRE

Sapphiretranslated from Greek means “blue”. Surprisingly, this piercing blue stone is the closest relative of the blood red ruby. This is also corundum, and its color is due to titanium impurities. When growing artificial sapphires, titanium is also added, but it is extremely difficult to recreate the variety of color shades with which nature has colored the gem: it is soft blue, deep blue, indigo blue, lilac. There are also stones that have the effect of asterism. Such crystals are called star-shaped; under certain lighting, a sparkling six-ray star lights up in them. The hardness of the stone on the Mohs scale is 9 points.

Sapphire is one of the four most expensive stones in the world. It is more common than ruby, often in the form of very large stones. The most prized are the clear cornflower blue Kashmir sapphires, which are famous for retaining their color under artificial light, which is rare for this crystal. The juicier and brighter the blue of natural sapphire, the higher its price. Sapphire is very hard and can only be scratched by a diamond, making it perfect for rings and bracelets.

The name of this stone comes from the Greek "sappheiros" - a blue or blue valuable stone, although the Greek word itself possibly comes from the Babylonian "sipru" - scratching. Previously, only blue corundums were considered sapphire. Now these include corundums of various colors: yellow, purple, green, orange and colorless, except red. The color of the stone, as a rule, is specifically specified: green sapphire, yellow sapphire, etc. Otherwise, only blue or cyan sapphire is meant.

The powers that be have always had a weakness for the delicate shine of sapphire. Thanks to its marvelous heavenly coloring, it was already considered sacred in Ancient Greece and Ancient Rome and dedicated to the father of all gods - Zeus. Only priests can wear it in a ring on their index finger; the stone helps them hear and understand what the oracle says. Indian high priests wear a sapphire pendant on their chest, and this ornament is called Truth.
According to the book of the great Exodus, the god Yahweh gave Moses the Ten Commandments, engraved on sapphire tablets (large stones). In the Middle Ages, sapphire was revered as a symbol of holiness, infallibility and inviolability of power; kings abundantly decorated their crowns and other regalia with it. Boris Godunov, a great lover of gems, considered it the most beautiful and powerful talisman.
Amazingly beautiful sapphires are stored in the Diamond Fund of Russia. One of them, “Imperial Power” (200 carats), is mounted in the cross of the power of the Russian Empire, the other, cornflower blue, weighing 258 carats, is inserted into a precious brooch.

EMERALD

Emerald- bright green beryl. Its green color is due to the presence of impurities of chromium, iron and vanadium. The hardness of the stone on the Mohs scale is 8. This is a very fragile gem, and often cracks and chips significantly reduce its quality. Therefore, the edges of the crystal are often covered with complex engravings to hide defects. Interestingly, this stone is almost always processed with a step cut, which is called emerald.

Emerald is a jewelry crystal of the highest class; many of them are more valuable than diamonds. The stone is especially valuable due to its density of color and transparency, the absence of inclusions and cracks.
Currently, artificial stones synthesized in Switzerland, France, and Germany are widely used in jewelry. Cut emeralds in jewelry, due to their uniform green color and strong shine, are not inferior to diamonds - both in cost and in their perfect beauty.
The green gem became famous as a talisman for mothers. They say he patronizes pregnant women. Egyptian priests ordered women expecting a child to wear a ring with an emerald and then place it in the cradle with the baby. People with poor memory and poor eyesight are advised to wear this mineral in necklaces and pendants around the neck, and it is better to wear a ring with it on the little finger.

Judging by the ancient Egyptian papyri, emerald has been known to man for at least 6.5 thousand years. From prehistoric times to this day, the gemstone has maintained a prominent position in the gem market, especially in the East, as it represents the sacred color of Islam. Emerald was Cleopatra's favorite stone. She presented close nobles with unique talismans with her image engraved on an emerald.

One of the most amazing legends about this stone is that the emerald fell from the head of Lucifer himself when he was expelled from paradise. The Holy Grail was carved from it, from which Christ himself drank at the Last Supper. On Golgotha, the blood of the crucified Jesus was collected in this cup, after which it acquired miraculous power - it bestowed many years of life on those who drank from it.

It is curious that the largest of the emeralds was found in 1970 in Ukraine. It was called “Jubilee Leninsky”. He weights 5360 g (26800 carats), like an impressive watermelon!

ALEXANDRITE

Alexandriteis a type of chrysoberyl, in Russia it is classified as a precious stone. It has a rare property - reverse, i.e. it changes color depending on the type of lighting: during the day its color range varies from dark blue to emerald green, and under artificial lighting alexandrite acquires a purple-red color.
Mohs hardness - 8.5.

The largest Russian alexandrite has a ton of everything 6 g . It is believed that the duality of the color of alexandrite is magically connected with the duality of human blood - arterial and venous, and the stone regulates hematopoiesis, purifies the blood and strengthens blood vessels. The ring with this stone should be removed before going to bed. Alexandrite makes its owner peaceful and accommodating.

If chrysoberyl matches its chemical formula exactly, it is pure and colorless, but this is exceptionally rare. Much more common are cloudy stones with a “cat’s eye” effect - cymophanes and varieties with a change in the color of the stone when the nature of the lighting changes (Alexandrite). Impurities of iron, chromium, and sometimes titanium cause the color of alexandrite to change from green tones in daylight to violet-red in electric light. In Russia, alexandrite is found as an associated mineral in the emerald mines of the Urals, where it was, in fact, first discovered.. Due to the rare occurrence and size of individual stones, there is no need to talk about its industrial mining in Russia. And in this regard, alexandrite is practically absent in domestic jewelry. Indeed, everything that is called alexandrite in the trade, upon closer examination, turns out to be synthetic corundum with the effect of changing color due to the addition of impurity elements. Alexandrite is found in much larger quantities in Brazil and Sri Lanka; the cost of large and clean stones can reach 20 thousand dollars.

AQUAMARINE

Aquamarineis a type of the mineral beryl. This stone shimmers in an unusually beautiful spectrum of light blue tones: from the light blue of the sky to the deep color of the sea. The color of the mineral can be compared to the color of sea water in tropical latitudes, and the color of the stone varies in different directions. When heated, aquamarine crystals can change their green outer color to a blue tint. A very wear-resistant, transparent and shiny stone, it always has high clarity, even if it is very large in size (although such stones are very rare). Dark blue aquamarine is always more expensive than light-colored stones. The light blue color of aquamarine awakens in us feelings of sympathy, trust, harmony and friendship. This color is divine, eternal, just like the color of the sky and the color of water, a color that gives the strength of life. It seems that the aquamarine has caught a piece of the ocean within itself. The main source of the most valuable dark blue stones is Brazil. Thanks to its mystical resemblance to sea water, aquamarine has long been considered a talisman for travelers. It is able to protect against seasickness and ensure safety on a sea voyage.

AMETHYST

Amethystbelongs to the quartz group and is silicon dioxide. Hardness on the Mohs scale -7.
Color varies from almost colorless pale violet, bluish violet to purple, dark violet, almost black. Interesting samples with a color transition along the length of the crystal from violet to yellow - ametrine.

Under the influence of sunlight, amethyst gradually loses its purple color and becomes discolored. When heated to a temperature of 300 degrees Celsius, it completely loses its beautiful purple color. The nature of its color is very complex - it is caused by a combination of iron ions and defects in the crystal lattice.

Amethyst is the most valuable mineral in the group of quartz varieties.

The name amethyst comes from the Greek amethystos, which means inebriated. At that time it was believed that wearing an amethyst was not subject to intoxication. In addition, there was a belief that if you drink from an amethyst goblet, there is no danger of poisoning. One of the earliest mentions of amethyst is that it was one of the twelve stones that adorned the breastplate of the Jewish high priest who served in the Temple of Jerusalem. For centuries, ancient Greek and Roman magicians and sages believed that it could prevent intoxication.

TURQUOISE

Turquoiseis an aqueous (hydrated) phosphate of copper and aluminum, but aluminum can be partially replaced by iron oxide. Turquoise, which does not contain iron, is colored blue in various shades - from sky blue to Prussian blue; the presence of iron usually gives the stone a greenish tint, which may intensify to the point where the mineral turns yellowish-green to apple green.
Regardless of the fashion for stones, turquoise has always been considered a talisman of health, happiness and good luck. Turquoise is an indicator of health.

Some stones fade and turn green when they change hands, thereby demonstrating amazing devotion to the previous owner.

Due to its relatively low hardness, turquoise is usually not cut and set into jewelry in the form of round stones of regular shape, called cabochons.

Turquoise (turquoise) owes its name to the French word Turkish (from pierre turquoise - Turkish stone). The Russian name comes from the Persian word “firuza”, which means “victorious, bringing happiness.”

Buddhists idolized turquoise because it was associated with the belief that it was thanks to it that Buddha was able to destroy the monster.

Turquoise was called the stone of victory and happiness. She was considered a military talisman. Turquoise was especially revered by the Aztec Indians of Central America: their leaders were buried with turquoise jewelry. Turquoise is the national stone of the Persian (Iranian) people; According to Persian beliefs, turquoise was formed from the bones of people who died of love. In Egypt, images of sacred scarab beetles were carved from turquoise. The name of the mineral itself comes from the Persian word “firuz” - “victorious”. The Armory Chamber of the Moscow Kremlin houses the throne of Tsar Boris Godunov with large inserts of first-class turquoise.

RHINESTONE

Rhinestone- crystals of transparent colorless quartz.

The term “crystal” is a Russified form of the Greek word “kristallos” - ice; It is in this meaning that it is used in the Iliad and the Odyssey. Later, but back in ancient times, transparent quartz, which was then considered strongly hardened ice, began to be called a crystal due to its external similarity. Even in the 12th century. Marbod of Rennes wrote: “Pure crystal is ice that has hardened over many years...” In Russian terminology, until the second quarter of the 19th century. “crystal” and “crystal” were synonymous and were even used together. Only later did natural polyhedrons of minerals begin to be called crystals, and “crystal” with the definition “mountain” was assigned to quartz. Heavy, highly refractive glass is simply called “crystal”.

Balls were cut out of crystals for ritual and magical purposes, incendiary lenses, with the help of which priests lit fire on altars with “divine fire,” and “magnifying glasses.” According to ancient beliefs, rock crystal relieves bad dreams, in a ring it protects from the danger of freezing, etc. In the Armory Chamber of the Moscow Kremlin there are various vessels made of rock crystal: the samovar of Peter I, a keg, a pepper shaker, a mug, bowls, “by hand,” etc. d.

POMEGRANATE

Pomegranate- a mineral of traditionally deep red color, a shade of “pure flame”, and high hardness. It is part of a group of silicates that vary greatly in color and contain various cations. In shape and color, the crystals resemble pomegranate seeds, hence its name. However, this gem is not only red.

There are six types of garnet: fiery pyrope, greenish demantoid, transparent lilac, purple or violet-red almandine, emerald green uvarovite, orange spessartine and grossular - the color of gooseberries.

Garnet is relatively inexpensive, and in beauty and depth of color it can easily compete with ruby ​​and emerald. Fiery red pyrope was very popular in the last century, but the release of a large quantity of the mineral onto the world market unfairly relegated it to a minor gemstone.

Modern products widely use garnets processed in various ways - faceted, cabochon, polished; The ancient form of cutting is very common - in the form of a saucer, which increases the transparency of the gem.

Interestingly, jewelry with garnets was known back in the Scythian era. Europe first learned about this stone thanks to the crusaders, who brought it from the Middle East. The ancient Persians wore garnets as protection from natural disasters; they considered these stones to be royal, and the profile of the ruler was often carved on the surface.

PEARL

Pearl- round or irregularly shaped shiny formations with a mother-of-pearl tint, which arise when layers of aragonite (calcium carbonate) are deposited around some foreign center, most often grains of sand, in the cavity of marine and freshwater mollusks that have a shell with a mother-of-pearl inner layer.

It is characterized by soft, delicate, faintly noticeable tints of color, a smooth matte surface and a bright spot of light on it, a natural spherical shape.

Color: white, pale pink, pale blue, pale green. It also comes in yellow, red, blue and even black. The ideal shape of a pearl is round. But there are also elongated, pear-shaped, irregularly shaped specimens.
diseases.

Nature gave pearls a short lifespan, lasting more than two or three human generations. To prevent pearls from aging, they must be worn, but should not be kept in bright sun for a long time.

Harvesting pearls from the bottom of the sea is a difficult and dangerous business. Among the 40-50 shells caught, only one contains a treasure. The price of a pearl increases tens of times for every millimeter in diameter, but its value is determined not only by its size, but also by its brilliance, color, and shape.
The world's most expensive pearl, La Regente, of perfect proportions and weighing 15.13g, the size of a golf ball, was sold at auction for $864,300. The largest is the “Pearl of Allah”, in shape and size resembling a head in a turban, weighing 6.5 kg, found in 1934. near the Philippines.
At the end of the 19th century, a young entrepreneur, Takiche Mikemoto, unraveled the secret of the birth of mother-of-pearl peas. He introduced a grain of sand into the shell and after a couple of years he received cultured pearls. With this he delighted women all over the world. More than 200 tons of cultured pearls are produced in Japan every year. Only special devices and unique craftsmen can distinguish it from natural ones.

Pearl jewelry has been known almost since prehistoric times—for 6,000 years.

TOPAZ

Topaz- a very hard (cuts glass) mineral aluminum fluorosilicate.
The color of the stones is determined by the admixtures of titanium, iron and chromium. The color range of topazes is very rich. They can be colorless, pink, yellow, golden, blue, red-orange, purple, wine, brown. There are yellow stones with a “cat's eye” effect. Polychrome minerals look very beautiful, in which one part can be blue and the other cherry. It has one more characteristic feature - faceted crystals are very slippery to the touch and easily slip out of your hands.

The word “topaz” comes from the Sanskrit tapas - “fire”, “flame”, “heat”.
Colored varieties of the mineral gradually fade from bright light, so it is better to store it in the dark.

Topaz has every reason to become a favorite - low price, high hardness and, of course, outstanding appearance. The most valued are: violet, as well as yellow, peach, orange and purple - they account for less than 0.1% of the total topaz market! The most popular are blue and blue varieties. Half a century ago, a method of refining was discovered that gives such shades greater brightness and depth. It is amazing that many colorless stones acquire a dazzling shine after cutting - they can easily be confused with a diamond!