| Mineral | Riebeckite |
|---|---|
| Formula | Na2[(Fe2+,Mg)3Fe3+2]Si8O22(OH)2 |
| Crystal Form | Monoclinic/Prismatic [2/m] |
| Cleavage | Perfect on {110} |
| Color | Black, dark blue, dark blue to yellow-green |
| Density | 3.3 – 3.4 g/cm3 |
| Diaphaneity | Translucent, Opaque |
| Fracture | Conchoidal - Uneven, Splintery |
| Hardness | 5.0 - 6.0 |
| Lustre | Vitreous - Silky |
| Streak | Pale gray to bluish-grey |
| Dana 8 Class | 66.01.03c.05 |
| Strunz Class | 8/F.08-50 |
| Mindat | mindat.org |
| WebMineral | WebMineral |
| ID | 209 |