Gemstone Characteristics
Tourmaline

Chemical Composition:
(Na, Ca) (Li, Mg, Fe, Al)9 B3Si6 (O1OH)31
Hardness: 7 - 7.5
Refractive Index: 1.62 - 1.64
Specific Gravity: 3.06
Lustre: Vitreous, Resinous.
Locations Where Found:
Russia, Brazil, Sri-Lanka.
Colours:
Red, Green, Blue, Yellow, Black, Brown, Colourless, Party Coloured.

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