Fassaite
| Fassaite | |
|---|---|
Fassaite from Val di Fassa | |
| General | |
| Category | Minerals |
| Formula | Ca(Mg,Fe,Al)(Si,Al)2O6 |
| Crystal system | Monoclinic |
| Crystal class | Prismatic (2/m) (same H-M symbol) |
| Space group | C2/c (no. 15) |
| Identification | |
| Color | light-dark green, black |
| Crystal habit | prismatic, short, plane |
| Mohs scale hardness | 6 |
| Streak | greenish-white |
| Specific gravity | 2.9-3.3 |
| References | |
Fassaite is a variety of augite with a very low iron content, Ca(Mg,Fe,Al)(Si,Al)2O6. It is named after the Fassa Valley, Italy.
It is thought to be a contact mineral formed at high temperature on the interface between volcanic rocks and limestone. It is also reported in meteorites.