1 Physical Properties
1.1 Tenacity
1.2 Solubility
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle, Conchoidal, Brittle
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), (e.g. graphite).
1.6 Cleavage
Perfect {10 1 0}
Distinct on {001} and {110}, indistinct on {100}
1.7 Mohs Hardness
1.8 Chemical Composition
(Na,Ca,K) 8(Si,Al) 12O 24(SO 4,Cl,CO 3) 3(H 2O)Arthur Thomas , Gemstones (2009)
Pb 2(CO 3)Cl 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references