Frohbergite
| Frohbergite | |
|---|---|
Frohbergite (Arizona) | |
| General | |
| Category | Telluride (sulfosalt) mineral |
| Formula | FeTe2 |
| IMA symbol | Frb |
| Strunz classification | 2.EB.10a |
| Crystal system | Orthorhombic |
| Crystal class | sulphide |
| Identification | |
| Color | white with a lilac or pinkish tint |
| Crystal habit | in the form of a thin border or small inclusions |
| Cleavage | the mineral is fragile |
| Mohs scale hardness | 3-4, up to 4.5 |
| Luster | metallic |
| Diaphaneity | opaque |
| Density | 8.057 (calculated) 8.055 (measured) |
| Pleochroism | extremely weak. |
Frohbergite (German: Frohbergit, title by proper name: Max Hans Frohberg), also iron telluride is a rare hydrothermal mineral from the sulfide class, in composition — iron telluride with the ideal formula FeTe2 (contains 82.05% tellurium and 17.95% iron).
Frohbergite occurs in tellurium-rich veins of hydrothermal deposits, sometimes as a thin rim on the periphery of chalcopyrite or as inclusions in native gold, petzite or chalcopyrite. It belongs to the marcasite group and forms a mineral line with mattagamite. Frohbergite most often occurs as fine-grained aggregates.: 93