1 Physical Properties
1.1 Tenacity
1.2 Solubility
Decomposed by acids
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Not Available
Conchoidal, Metallic, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
1.6 Cleavage
Perfect on {010}
Fair in four directions forming octahedrons
1.7 Mohs Hardness
1.8 Chemical Composition
(K,Na)3Cu20Al3Si29O76(OH)16•~8(H2O)
Cu 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references