Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
perfect along [010] and [100]
Cu 5(SiO 3) 4(OH) 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
SiO 2 · nH 2OWalter Schumann , Gemstones of the world (2001) More from other references