Pyroxmangite
| Pyroxmangite | |
|---|---|
Pyroxmangite from Chubu Region, Honshu Island, Japan | |
| General | |
| Category | Inosilicate |
| Formula | MnSiO3 |
| IMA symbol | Pxm |
| Strunz classification | 9.DO.05 |
| Crystal system | Triclinic |
| Crystal class | Pinacoidal (1) (same H-M symbol) |
| Space group | C1 |
| Unit cell | a = 9.69 Å, b = 10.5 Å, c = 17.39 Å; α = 112.17°, β = 102.85°, γ = 82.93°; V = 1,596.00 Å3; Z = 28 |
| Identification | |
| Color | pink, red, brown |
| Twinning | Lamellar on {010}, simple on {001} |
| Cleavage | Perfect on {110}, {110}, (110) ^ (110) = 92° poor on {010}, {001} |
| Fracture | hackly, uneven |
| Tenacity | brittle |
| Mohs scale hardness | 5+1⁄2 – 6 |
| Luster | vitreous, pearly |
| Streak | colorless |
| Diaphaneity | transparent, translucent |
| Specific gravity | 3.8 |
| Birefringence | δ=0.018 |
| Other characteristics | morphology: tabular crystals, granular massive, grainy |
| References | |
Pyroxmangite has the general chemical formula of MnSiO3. It is the high-pressure, low-temperature dimorph of rhodonite.
It was first described in 1913 and named for the mineral group, pyroxenes, and is known as the manganese member. It forms a series with pyroxferroite.
Pyroxmangite occurs in metamorphosed ore deposits rich in manganese. Associated minerals include spessartine, tephroite, alleghanyite, hausmannite, pyrophanite, alabandite, rhodonite and rhodochrosite.