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New Arrivals
10.03.2024

Tourmalines from Afghanistan

We present to your attention new items from the GEM INDUSTRY stone catalog – Afghan tourmalines of various colors, cut shapes, weight, purity and rarity.

Tourmaline is a very colorful variety of stones that can be found in many places around the world. It is a durable crystal that is very rarely treated to enhance its appearance and can range in price to suit any budget.

Mining conditions in Afghanistan are quite difficult and it is not easy to extract tourmaline from the mines, which also contributes to higher prices for Afghan tourmaline. Your GEM INDUSTRY

Tourmaline comes in many colors. Iron-rich tourmalines range in dark shades from bluish-black to dark brown, while magnesium-rich varieties range from brown to yellow. Lithium tourmalines are available in almost any color: blue, green, red, yellow, pink, etc.

Turmaliny, naydennyye v Afganistane do sikh por, byli rozovogo, zelenogo i sinego tsvetov, vklyuchaya neskol’ko nebol’shikh, no vpechatlyayushchikh nakhodok indigolitovykh turmalinov v provintsii Nuristan, a takzhe potryasayushchiye obraztsy myatno-zelenogo i golubogo turmalina laguny. Tourmalines found in Afghanistan so far have come in pink, green and blue colors, including several small but impressive finds of indigolite tourmalines in Nuristan Province, as well as stunning examples of mint green and blue lagoon tourmaline.

Encyclopedia of stones
17.01.2024

Semi-precious stones starting with the letter “A”

Discover a world of stones and minerals from all over the world! Узнайте об их визуальных особенностях, основных характеристиках, месторождениях и истории.

Semi-precious stones, or, as they are also called, jewelry and ornamental stones, are more often used in the production of jewelry than in souvenirs and sculptures.

As usual, let’s start with the first letter of the alphabet! Your GEM INDUSTRY

The kingdom of minerals and rocks is an independent kingdom of nature on our planet, as important and interesting as the kingdoms of animals and plants. It was the rocks that formed the hard shell of the Earth and became the basis on which the soil appeared; it is from them that metal and building materials are extracted, and magnificent jewelry is created. Thousands of minerals and the crystals formed by them are known to scientists today, and dozens of new ones are discovered every year.

Aquamarine

Aquamarine (lat. aqua marina – sea water) is a mineral, a type of beryl, beryllium aluminosilicate with a ring structure. In the structure of aquamarine, like all beryls, there are rings [Si6O18] regular hexagonal shape, located one above the other and forming hollow channels.

Aquamarines are mined from pegmatites, often found in coarse-grained granites.

Deposits are known on all continents, the most significant: Brazil (Minas Gerais, Bahia, Espirito Santo), Madagascar, Russia (Urals, Transbaikalia).

Aquamarines are also found in smaller quantities in other countries: Australia (New South Wales), Myanmar, Sri Lanka, India, Kenya, Namibia, Mozambique, South Africa, Tanzania, Ukraine (Volyn), USA (Colorado, Connecticut, California, Maine, North Carolina).

The largest gem-quality crystal was found in 1910 in Brazil (weight 110.2 kg, 48.2×41 cm). 220 thousand carats of cutting material were obtained from it. A little earlier, an aquamarine weighing 18 kg, called “Jacketeau”, was found there, from which about 30 thousand carats of jewelry material was obtained.

Amethyst

Amethyst (ancient Greek αμέθυστος, from α- “not” + μέθυστος “to be drunk”) is a purple, bluish-pink or red-violet variety of quartz. Transparent amethyst is a semi-precious stone. Opaque – a valuable ornamental stone. It is highly valued as a collectible mineral.

It is usually found in the form of crystals and their intergrowths freely sitting in voids and veins among crystalline rocks. The crystals are formed by a combination of prism and rhombohedral planes, and of all quartz, amethyst is characterized by the predominance of rhombohedral faces. Less commonly, crystals have a long prismatic or scepter-shaped appearance. Common in drusen and crystalline brushes within agate geodes and in tonsils and fissures in volcanic rocks.

Amethyst deposits are found near Oberstein in Birkenfeld, in Zillertal, in Siebenbürgen, Chemnitz, near the villages of Vatikha and Lipovaya near Murzinka in the Middle Urals, large crystals of jewelry quality in the Subpolar Urals, on the island of Sri Lanka, near St. Mary’s Bay, in North America and in particularly significant quantities in Brazil. Also in Madagascar, Uruguay, Armenia (brushes of small crystals in agate geodes). Amethyst has been known since the 16th century on the Kola Peninsula: in the famous “Cape Ship” deposit (where it forms beautiful brushes of crystals along cracks in red sandstones), as well as in a number of quartz deposits (Vuorijärvi, etc.), as well as in Brazil.

Apatite

Apatite (from the Greek ἀπάτη “apati” – deception) is a group of minerals of the phosphate class, with the chemical formula Ca10(PO4)6(OH,F,Cl)2, the main component of apatite ores rich in phosphorus (agronomic ores). A mineral containing variable amounts of fluorine, chlorine, OH-, or more precisely, a common name for a number of related minerals of the apatite group with the general formula Ca5(PO4)3(F,OH,Cl).

Industrial deposits of apatite are rare. The world’s largest deposit is Khibinskoye on the Kola Peninsula in Russia, where apatite ores are mined, consisting mainly of fluorapatite and nepheline (apatite nepheline ore). Also known are the Oshurkovskoye and Beloziminskoye deposits in Buryatia, and the Seligdarskoye, Neryandzhinskoye and Ulkhan-Melenkinskoye deposits in Yakutia.

Large, well-formed crystals of apatite (the so-called moroxite) are known from the Slyudyanka deposit (near the city of Slyudyanka in the south of the Irkutsk region).

Apatite deposits are also known in Brazil, Mexico, USA, Chile, South Africa, Finland, Spain, Norway and other areas of the world.

Of course, this list is not complete and will be regularly updated with minerals, rocks, meteorites, as well as stones that cannot be classified as one or the other.

The encyclopedia will put everything in its place: it will teach you how to identify the types of minerals and rocks, tell you the places where they can be found, and tell you how they are used. Follow our news!

Certification
17.10.2023

Certification of semi-precious stones

Legal requirements

Semi-precious stones do not fall under the GOST R and TR TS systems. However, semi-precious stones require mandatory quality assessment in profile systems, as well as marking and sealing.

Voluntary certificates

Such certificates are usually issued in accordance with GOST R or ISO. There are two main state standards that can be used to assess the quality of semi-precious stones:
  • GOST R 51519.1-99 “Rough natural diamonds. Classification. Main features”;
  • GOST R 52913-2008 “Diamonds. Classification. Technical requirements”.
There are a large number of technical conditions and service stations that can be used to check.

Certification procedure

Certification is carried out in the following order:
  • Submitting an application to the gemological center;
  • Formation of a package of documents, development of technical documentation (if necessary);
  • Selection of stone samples, laboratory tests, generation of test reports;
  • Issuance of a certificate.
The package of documents includes the name and description of semi-precious stones, codes assigned to them, previously issued permits, seller details, technical documentation and an application for inspection.
Interesting Facts
17.07.2023

Types of stone cuts

In total, there are 3 types of cuts (facet, circle and cabochon), which number more than 250 varieties. The choice of processing depends on many factors, such as the type and size of the mineral, its hardness, purity, optical properties and, of course, the skill of the cutter.

The history of gem processing dates back to antiquity and continues to this day. During this time, craftsmen have created more than one device for giving beautiful shapes to precious minerals, and there are hundreds of types of stone cuts. Why is there such diversity and what are the most popular processing methods?

We will look at several of the most spectacular types of cutting of semi-precious stones.
Your GEM INDUSTRY

Circle — This is a classic, especially in diamond cutting. The shape is highly valued in the market. Its most popular variety and standard is the diamond cut with 57 facets, 33 of which make up the crown. It is used for working with large gems. On smaller ones, from 33 to 17 sides are created.

Oval — modification of a circle with the same number of sides. Appeared in the second half of the 20th century. Thanks to the larger area, it allows you to better reveal the properties of the stone.

Pear — another modification of the circle, similar to a drop. Features a flat base with 1 acute angle. Has 1 less face than a circle. Known since the 15th century.

Emerald — a stepped rectangular treatment that takes its name from the gem for which it was created. It is considered one of the oldest types of stone cutting and has been known since the 13th century. It has 8 facets in the girdle. The total number of faces is usually 65. The large platform of “Emerald” allows you to maximize the beauty of transparent minerals with a high level of purity.

Asher — A variety of emerald cut that has a square shape and more tiers. This type of cut was invented by the Asscher brothers, hence the name. Asscher cut diamonds were very popular back in the 1920s, which is why they are mostly seen in antique stores.

Princess — a more elegant and iridescent variety of the square cut. It differs from the classic “square” in a different direction of the ribs. They are created both along the outer contour and in the center of the gem. The number of faces is 49, 57 or 65. Varieties – “Nissen”, “Quadrillion”, “Bagvillion”.

Marquis — a type of diamond-cut stone similar to the shape of a biangular boat. Number of sides 55–57. According to legend, this form was created in France during the reign of Louis XV to process a gem as a gift to the king’s favorite, Marquise De Pompadour.

Heart — romantic shape with sophisticated diamond processing technology. According to the standard, there are at least 57 sides, so large minerals are taken to create the heart. Used since the 16th century.

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