| Tantite | |
|---|---|
| General | |
| Category | Oxide minerals |
| Formula | Ta 2 O 5 |
| IMA symbol | Tan [1] |
| Strunz classification | 4.EA.05 |
| Dana classification | 04.06.06.01 |
| Crystal system | Triclinic |
| Crystal class | Pedial (1) (same H-M symbol) |
| Space group | P1 |
| Unit cell | a = 3.8 Å, b = 3.79 Å c = 35.74 Å; β = 90.18°; Z = 6 |
| Identification | |
| Formula mass | 441.89 g/mol |
| Color | Colorless |
| Cleavage | None |
| Mohs scale hardness | 7 |
| Luster | Adamantine |
| Streak | White |
| Diaphaneity | Transparent |
| Specific gravity | 8.55 |
| Density | 8.45 g/cm3 |
| Optical properties | Biaxial |
| References | [2] [3] |
Tantite is a rare tantalum oxide mineral with formula: Ta 2 O 5. 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.