Tourmalines are precious gems, eye-catching colour palette and amazing attractiveness of existing varieties. Minerals have the form of prismatic crystals. For they are characterized by longitudinal hatching and rounded triangular cross section.
Tourmalines have relatively high hardness, component of 7-7,5 on the Mohs scale and a wonderful Shine. These qualities contribute to the wide use of gem jewelers. Minerals bright rich in color and good purity, with a mass in excess of 10-15 carats are extremely rare. These tourmalines belong to the higher price category. The designers of the leading jewelry companies regularly apply them when creating their collections.
Tourmalines can have the following optical effects:
The effect of "cat's eye" due to the presence of thin canals, filled with inclusions of gas and liquid consistency. Found among tourmalines green color;
The presence of "alexandrite" effect, representing a change of colors when changing the light source depends on the presence of chromium impurities. It is possible to observe a yellow-green color of the tourmaline under sunshine and orange-red tones when you turn on artificial lighting.
Tourmalines have a very complex chemical composition, due to the possibility of substitution of the atomic structure of the crystal lattice without disturbances of its structural form. Experts gemologists made a division of the family of tourmalines into several groups differing in chemical composition:
Sherly – ferrous minerals black color;
Gravity – magnesian tourmaline brown, more rarely green or black color;
Colors – gems containing impurities of sodium and lithium which give the crystals pink, yellow, green or polychrome shades. Most jewelry tourmalines belong to this group;
Uvita is similar to DrawItem in which there is predominance of calcium over sodium. There are instances of green, brown, black;
Liddicoatite – similar to elbaite. The only difference is the greater content of calcium and not sodium. Refer to jewelry gems with pink and green zonal coloration in the form of strips;
Kromdraai – are different colors from dark green to black tones.
Participants of the market of precious gems is almost not used the names of these groups. Note that the color and some other physical properties of tourmalines depend on the chemical composition of minerals. The presence of iron ions or titanium characteristic blue, blue, green, yellow, orange, brown, brown crystals. Emerald green tone depends on the presence of chromium ions or iron. In minerals pink and red color is present, the admixture of manganese.
In the jewelry market it is customary to use the classification of tourmalines on the color palette:
Rubellites – tourmalines have pink or red coloring. Are among the leaders in growth value in the jewelry market. Color scheme ranges from light pink to deep pink, crimson, scarlet, purple and red tone. Rubellites with deep shades of red refers to the highest price category. Cost some instances can exceed $ 1,000 per 1 carat. This raises the rubellites on the second place in value among types of tourmaline, straight after the neon blue of Paraiba tourmaline. Interesting fact – pink rubellites high quality prefer the Japanese and the red Chinese. Sustained high demand for rubellite in Asia, Europe and the United States annually increases its cost. For rubellites characterized by the presence of a large number of inclusions, representing the gas-liquid veils. Instances of high purity, without impurities, are estimated very highly.
Indigolite – tourmaline blue, greenish-blue, bluish-blue color. Are a fairly rare variety of the mineral. The stones of rich blue color graded the most expensive. Indigolite come from Brazil, Afghanistan, Pakistan, Mozambique and Nigeria. The price of the best gems can exceed a thousand dollars per 1 carat.
Verdelite – variety of tourmalines from dark green to light green, pastel "mint" colors. Verdelite usually have a high purity, it is the most popular variety.
Fromtermini – have a bright green or rich green color, depending on the presence of the admixture of chromium. Fromtermini brighter verdelite and valued several times higher. Read more about fromturning can be read under Verdelite
Paraiba - the most expensive tourmaline. For details, visit stone.
The elevation of tourmalines
Experts are not engaged in the synthesis of tourmalines. Various methods of refinement are used to improve the quality of color stones. Heat treatment is used for lightening of dark green tourmaline or blue-green colors. With strong heating of tourmalines pink-red hue, they are completely discolored. In view of this, through heat treatment at low temperature are the dark stones. The effects of temperature removes all the unnecessary colours pink and purple tones in the tourmaline of Paraiba, leaving a beautiful blue and greenish-blue tones.
The technology of irradiation is required when improving the color saturation of tourmalines pink tones. In addition, irradiation of colorless stones gives them a pink hue, and the irradiation light yellow tourmalines adds to their brightness. Specialists, use technology, crack filling polymer, in order to visually improve the purity of the stones. This technology processed the Paraiba tourmaline after heat treatment, with significant amount of cracking. Discoloration of the channels in the rocks is produced by etching with acid. Diagnostic conclusion to the lab you need to buy tourmalines, Paraiba particularly expensive because the fact of gentrification significantly affects the cost of the stones.
Deposits of natural tourmalines
Note the large number of deposits of tourmalines in the world. The bulk of high-quality stones for jewelers comes from Brazil. In addition, deliveries are from Mozambique, Madagascar, Nigeria, Afghanistan, Tajikistan, Pakistan. Extraction of Russian tourmalines produced in the Urals.
Interesting facts about tourmaline stone
The first copies of tourmalines came to European countries from Ceylon (Sri Lanka) at the beginning of the XVIII century. Familiarity with these amazing stones, the Europeans are obliged by Dutch sailors. I wonder what the sailors used tourmalines to clean the pipes. It turns out that when heating is the electrification of the gems, and they extend the ash cleaning of the tube. A variety of colors tourmaline has led to the fact that they were often confused with other minerals of similar color. Popular in Europe and in Russia came to a pink-red tourmaline in the middle of the XVIII century. This contributed to a lot of wonderful jewelry and decorative items made by the jeweller Carl fabergé.
Jewelry embellished with tourmalines came into fashion in the XVIII century. These gems have been repeatedly confused with other precious stones used to decorate the crowns of kings and emperors. Contemporary jewelry brands regularly produce collections with tourmaline. Here are only decorations with these beautiful gems almost never occur in the Windows of the Russian jewelry stores. It's in a rarity jewelry tourmalines compared to amethysts, citrines or blue Topaz. Almost all jewelry with tourmalines exclusive. Often sold different models of earrings and rings with tourmalines, but jewelry sets seldom available.Huge popularity of all kinds of jewelry made of the famous brands Tiffany & Co, Van Cleef & Arpels, Chopard, Bulgari.
Buy natural tourmaline in Moscow
In our catalog you will always find excellent specimens of natural color tourmalines of all varieties, will be able to compare prices and to understand the approximate budget for future purchases.