Tourmaline has an excellent richness in color variation that no other gemstone offers. It exists in virtually every color possible. As the colors are in vast numbers, so are the combinations of elements, which are responsible for those colors. Commonly tourmaline is referred to with their body color instead of the variety name. For example, a colorless tourmaline is called as colorless or white tourmaline instead of Achroite. Because of its variety of colors, tourmaline is often confused with other gemstones but is high double refraction and strong pleochroism makes it different from them. The colors of tourmaline along-with their localities are explained below.
Chemical Composition: Complex Borosilicate
Crystal Structure: Trigonal
Hardness: 7.5
Specific Gravity: 3.06
Refractive Index: 1.62-1.64
Luster: Vitreous
Colors: -
ACHROITE: Colorless or nearly colorless. Considered quite rare. Achroite is found in Madagascar and Pala (California in USA).
DRAVITE: Yellow brown or dark brown. Mainly found in Sri Lanka. It is also found in Canada, USA, Brazil, Mexico and Australia.
GREEN & YELLOW TOURMALINE: Known by their body colors, green and yellow tourmalines are the most common of all tourmaline varieties. The green tourmaline is found in Brazil, Tanzania and Namibia. Yellow tourmaline is found in Sri Lanka.
INDICOLITE: Blue in all shades. Siberia (Russia) is an important source for indicolite. A lilac to violet blue or reddish blue variety is known as siberite. Fine bright indicolite has been recently discovered in Paraiba, Brazil. Other locations are Madagascar and USA.
RUBELLITE: Pink to red, sometimes with a violet hue. Also comes in ruby color, which is considered as the most valuable tourmaline. Rubellite is found in Russia along-with some other locations, which are Madagascar, Brazil, Burma, USA and East Africa.
SCHORL: Black. This kind of tourmaline is very common and has no significance as a gemstone and thus, it is not used in jewelry.
WATERMELON TOURMALINE: Tourmaline with more than one color. Combination of two colors known as bi-color tourmaline and combination of three colors is known as tri-color tourmaline. More colors or shades are also seen. Watermelon tourmaline is found in South Africa, East Africa, Brazil and many other locations around the world.
Astrological Relevance:
Tourmaline is considered to be one of the birthstones for the month of October, which covers two zodiac signs: Libra (September 22 to October23) and Scorpio (October 23 To November 21). |