![]() | You can help expand this article with text translated from the corresponding article in German. Click [show] for important translation instructions.
|
Tsilaisite | |
---|---|
General | |
Category | Tourmaline |
Formula | NaMn2+3Al6Si6O18(BO3)3(OH)3OH |
IMA symbol | Tsl [1] |
Crystal system | Trigonal |
Identification | |
Mohs scale hardness | 7 to 7.5 |
Luster | Vitreous |
Streak | White |
Tsilaisite is a manganese rich variety of elbaite tourmaline. [2] It is also known as Tsilaizite. [3] Tsilaisite is related Fluor-tsilaisite. [4] The gem is named after the location it was first found. [5]
It was first reported in the Tsilaisina (also called Tsilaizina) Mine in Vakinankaratra, Madagascar. [3]
The gem was originally described as tsilaisite. But then it was discredited in 2006. In 2011 it was reapproved as tsilaisite. [5]
In plane polarized light, the gem is pleochroic. [6] Tsilaisite can be deep pink, red, [2] orangish-yellow, brownish-gold, [3] or greenish-yellow. [5]
Manganese makes up to 3% of the gem's chemistry. [3]