Cristobalite
ID: 127
Cristobalite
Chemical Formula
SiO2
Hardness (Mohs)
6-7
Crystal System
Tetragonal / Orthorhombic
Streak
White
Luster
Vitreous
Diaphaneity
Transparent to translucent
Color
White, colorless, grey
Crystal Habit / Mode of Occurrence
Octahedral, cubic-like crystals; spherulitic, massive
Fun Facts
Cristobalite is a high-temperature polymorph of quartz, forming at temperatures above 1470 °C.