| Mineral | Gadolinite-(Y) |
|---|---|
| Formula | Y2Fe2+Be2Si2O10 |
| Crystal Form | Monoclinic/Prismatic [2/m] |
| Color | Black, Greenish-black, Brown, Grass-green to Olive-green in thin fragments |
| Density | 4.4 – 4.8 g/cm3 |
| Diaphaneity | Opaque, nearly transparent in thin fragments |
| Fracture | Splintery, Conchoidal |
| Hardness | 6.5 - 7.0 |
| Lustre | Vitreous, Greasy |
| Streak | Greenish gray |
| Type Loc. | Ytterby, Resarö, Vaxholm, Uppland, Sweden |
| Dana 8 Class | 54.2.1b.3 |
| Strunz Class | 8/B.29-50 |
| Mindat | mindat.org |
| WebMineral | WebMineral |
| ID | 375 |