Color: purple, green, colorless, white, yellow, pink, red, blue, or black
Streak: white
Hardness: 4
Specific gravity: 3.1–3.3
Cleavage: perfect octohedral
Fracture: conchoidal
Luster: vitreous
Crystal form: cubic or octahedral
Transparency: transparent or translucent
Forms in hydrothermal veins and around hot springs.
For an explanation of the properties (in bold face), click here >>