Tantite

Tantite is a rare tantalum oxide mineral with formula: Ta2O5. Tantite forms transparent microscopic colorless triclinic - pedial crystals with an adamantine luster. It has a Mohs hardness of 7 and a high specific gravity of 8.45. Chemical analyses show minor inclusion (1.3%) of niobium oxide.It was first described in 1983 for an occurrence in a pegmatite in the Kola peninsula, Russia. It has also been reported from a pegmatite complex in Florence County, Wisconsin. Associated mineral species include elbaite, lepidolite, spodumene, columbite-tantalite, wodginite, and microlite.
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General Information:
 Chemical Formula:
Ta2O5
 Composition:
(Molecular Weight = 441.89 gm)
Tantalum 81.90 % Ta
Oxygen 18.10 % O 
 Empirical Formula:
Ta2O5
 Environment:
Granitic pegmatites.
 Locality:
Kola region, Russia.
 Name Origin:
Named for its composition (Tantalum).
Physical Properties:
 Cleavage:
None
 Color:
colorless.
 Density:
8.45
 Diaphaniety:
Transparent
 Habits:
Microscopic Crystals - Crystals visible only with microscopes., ,
 Hardness:
7 - Quartz
 Luminescence:
Non-fluorescent.
 Luster:
Adamantine
 Streak:
white
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