Tephroite | |
Chemical Formula |
Mn2SiO4 |
Species |
Silicates |
Crystal System |
Orthorhombic |
Mohs Scale |
6 |
Specific Gravity |
3.87-4.12 |
Color |
Olive-green, bluish green, gray, °esh-red, reddish brown; pale green in thin section, may be colorless |
Streak |
Pale gray |
Luster |
Vitreous, Greasy |
Refractive Index |
n = 1.759 n = 1.797 n = 1.860 |
Diaphaneity |
Translucent |
Cleavage |
Distinct/GoodDistinct on Imperfect on |
Fracture |
Irregular/Uneven, Conchoidal |
Crystal Habit:Crystals typically short, prismatic, to 4 cm, or anhedral, equidimensional. Commonly in disseminated grains, compact, or massive. | |
Geological Setting:In Fe-Mn ore deposits, skarns, and metamorphosed manganese rich sediments. |