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Mineral Guide > Mineral Gallery > Tourmaline gem stone
Tourmaline gem stone A name applied to a group of double silicates composed of many other minerals. The color of tourmaline varies with their composition. The red, called rubellite, are manganese tourmaline containing lithium and manganese, with little or no iron; the violet, blue, and green contain iron, and the black are either iron or magnesium-iron tourmalines. Sometimes the crystals are red at one extremity and green at the other, or green internally and red externally, or vice versa. Pink crystals are found in the island of Elba. Tourmalines are not often used in jewelry, although they form beautiful gems and bear a high price. A magnificent group of pink tourmalines, nearly a foot square, was given by the King of Burmah to Colonel Sykes while commissioner to his court. The tourmaline appears to have been brought to Europe from Ceylon by the Dutch about the end of the seventeenth century, and was exhibited as a curiosity on account of its pyroelectric properties. Pink Tourmaline Rubellite picture |
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