Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
[010] Perfect, [100] Distinct, [011] Distinct
Amethyst, Clear Quartz, Smoky Quartz, Cacoxenite, Rutile, Geothite, Lepidocrocite
1.04 x 10−25 g per 100 ml water (Ksp at 25°C = 2 x 10−32)
Prismatic {10 1 0}, perfect
HgSMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references