 Tourmalines are gems with a wide variety of colors. The name tourmaline comes from the Singhalese words 'tura mali'. In translation, this means something like 'stone with mixed colors', referring to the color spectrum of this gemstone, which outdoes that of all other gemstones. There are tourmalines from red to green, and blue to yellow. Tourmaline is the birthstone for October and corresponds to the astrological sign of the Libra. They are said to be the 8th anniversary gift.
All tourmaline gemstones display plechroism, meaning their color changes when viewed at different angles. In some gems, this effect is hardly noticeable, while in others it is highly evident. Gemstone cutters take this into account when cutting a tourmaline, so the finished gem brings out its best color. There are tourmalines which change their color with light changes from daylight to artificial light, and some show the light effect of a cat's eye.
Tourmalines are mixed crystals of aluminium boron silicate with a complex and changing composition. The mineral group is a complex one. Even slight changes in the composition cause completely different colors. Crystals of only a single color are fairly rare; indeed the same crystal will often display various colors and various shades of colors. For example, a tourmaline that is intense red is known as a rubellite, but only if it continues to display the same fine ruby red in artificial light as it does in daylight. If the color changes when the light source does, the stone is called a pink or shocking pink tourmaline. In the language of the gemologists, blue tourmalines are known as 'indigolites', black ones as 'schorl' and yellowish-brown to dark brown ones as 'dravites'. One particularly popular variety is known as a 'verdelite' in the trade. This is known as green tourmaline. However, if its fine emerald-like green is caused by tiny traces of chrome, it is referred to as a 'chrome tourmaline'. Pariaba tourmaline is the most sought after tourmaline today. It is a variety that was discovered in 1980s in Brazilian mines of Pariaba.
This gemstone has excellent qualities and is easy to look after, for all tourmalines have a good hardness of 7 to 7.5 on the Mohs scale.
Tourmalines have some interesting scientific properties, including a charge at either end or the ability to carry electricity – called pyro-electricity or piezoelectricity. The charge can change under pressure or high temperatures, at which times the crystal can begin to vibrate. They are often used in machinery that measures pressure, as well as for their unusual optic properties, to polarize light.
There are major deposits in Brazil, Sri Lanka and South and south-west Africa. Other finds have been made in Nigeria, Zimbabwe, Kenya, Tanzania, Mozambique, Madagascar, Pakistan and Afghanistan. Tourmalines are also found in the USA, mainly in California and Maine.
Tourmaline in history :
Many gemstones in the Russian Crown jewels from the 17th Century that were thought to be rubies are in fact tourmalines.
In South America, where a majority of such gem-quality material is found, green tourmaline is still referred to as the "Brazilian emerald".
Tourmaline was prized as a gem through history, but her main admirer was Tzu Hsi, the Dowager Empress who ruled China from 1860 to 1908, and then wielded her power until her death in 1911. This last Empress of the Ch'ing Dynasty loved this stone so much that she bought enormous quantities of it when a new mine opened in California. Even now, her body rests eternally on a tourmaline pillow.
Tourmaline legends :
Tourmalines are believed to have the power to enhance one's understanding, increase self-confidence and amplify one's psychic energies, and aid in concentration and communication.
Conversely, they are said to neutralize negative energies, and dispel fear and grief.
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