Hedenbergite
| Hedenbergite | |
|---|---|
| General | |
| Category | Inosilicate minerals (single chain) |
| Group | Pyroxene group, clinopyroxene subgroup |
| Formula | CaFeSi2O6 (CaFe(SiO3)2) |
| IMA symbol | Hd |
| Strunz classification | 9.DA.15 |
| Crystal system | Monoclinic |
| Crystal class | Prismatic (2/m) (same H-M symbol) |
| Space group | C2/c |
| Identification | |
| Formula mass | 248.09 g/mol |
| Color | Brownish green, black |
| Crystal habit | Massive, prismatic crystals |
| Cleavage | Good on {110} |
| Fracture | Irregular |
| Tenacity | Brittle |
| Mohs scale hardness | 5.5–6.5 |
| Luster | Vitreous, dull |
| Streak | White, gray |
| Diaphaneity | Transparent-Opaque |
| Density | 3.56 g/cm3 |
| Optical properties | Biaxial (+) |
| Refractive index | nα = 1.699 – 1.739 nβ = 1.705 – 1.745 nγ = 1.728 – 1.757 |
| Birefringence | δ = 0.029 |
| Pleochroism | Weak |
| Dispersion | r > v strong |
| References | |
Hedenbergite, CaFeSi2O6 (CaFe(SiO3)2), is the iron-rich end member of the pyroxene group having a monoclinic crystal system. The mineral is extremely rarely found as a pure substance, and usually has to be synthesized in a lab. It was named in 1819 after M.A. Ludwig Hedenberg, who was the first to define hedenbergite as a mineral. Contact metamorphic rocks high in iron are the primary geologic setting for hedenbergite. This mineral is unique because it can be found in chondrites and skarns (calc–silicate metamorphic rocks). As a member of the pyroxene family, it has generated considerable interest due to its significance in general geologic processes.