| Sursassite | |
| Category: | Sorosilicate |
| Formula: | Mn2+2Al3(SiO4)(Si2O7)(OH)3 |
| Imasymbol: | Ss[1] |
| Strunz: | 9.BG.15 |
| Color: | Red-brown to copper-red |
| Habit: | Botryoidal |
| System: | Monoclinic |
| Class: | Prismatic (2/m) (same H-M symbol) |
| Symmetry: | P21/m |
| Cleavage: | [101] Distinct |
| Mohs: | 3 |
| Luster: | Silky, Dull |
| Refractive: | 1.73 to 1.76 |
| Opticalprop: | Biaxial |
| Birefringence: | 0.030 |
| Dispersion: | r > v |
| Pleochroism: | Strong; X = Z = colorless to pale yellow; Y = deepgolden brown. |
| Streak: | yellow-brown |
| Density: | 3.256 |
| Diaphaneity: | Translucent |
| References: | [2] [3] |
Sursassite is a sorosilicate mineral. It was first discovered in 1926.[4] It was first found in the Sursass (Oberhalbstein), a district of Graubünden, Switzerland. It is generally found in deposits of metamorphosed manganese.[5]