augite
Physical Properties
| Color | black |
| Form/Habit | massive |
| Lusture | vitreous |
| Streak | white |
| Hardness | 5-6 |
| Cleavage | perfect two sets |
| Fracture | uneven |
| Specific Gravity | 3.2-3.4 (moderate) |
| Chemical Composition | |
| Crystal System | monoclinic |
| Diagnostic Properties | perfect two set cleavage |