Sursassite
Appearance
Sursassite | |
---|---|
General | |
Category | Sorosilicate |
Formula (repeating unit) | Mn2+2Al3(SiO4)(Si2O7)(OH)3 |
Strunz classification | 9.BG.15 |
Crystal system | Monoclinic |
Space group | Monoclinic - prismatic H-M Symbol (2/m) Space group: P 21/m |
Identification | |
Color | Red-brown to copper-red |
Crystal habit | Botryoidal |
Cleavage | [101] Distinct |
Mohs scale hardness | 3 |
Luster | Silky, Dull |
Streak | yellow-brown |
Diaphaneity | Translucent |
Density | 3.256 |
Optical properties | Biaxial |
Refractive index | 1.73 to 1.76 |
Birefringence | 0.030 |
Pleochroism | Strong; X = Z = colorless to pale yellow; Y = deep golden brown. |
Dispersion | r > v |
References | [1][2] |
Sursassite is a sorosilicate mineral. It was first discovered in 1926.[3] It was first found in the Sursass (Oberhalbstein), a district of Graubünden, Switzerland. It is generally found in deposits of metamorphosed manganese.[4]
Notes
- ^ Pierre Perroud. "Sursassite". Athena Mineralogy: Mineral Data.
- ^ Sursassite details from Handbook of Mineralogy
- ^ Schweizerische mineralogische und petrographische Mitteilungen (1926), 6, 376-380.
- ^ Barthelmy, Dave. "Sursassite Mineral Data". WebMineral. Retrieved 2009-03-17.