Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
2.50-2.805.9-6.3
1
7.18
👆🏻
Fracture
-
Conchoidal, Uneven
Cleavage
Perfect
On {101}, distinct; on {112}, interrupted; on {001}, indistinct
Mohs Hardness
5-6.54.5-5
2
10
👆🏻
Chemical Composition
Na 4(Al,Si) 12O 24Cl to Ca 4(Si,Al) 12O 24(CO 3,SO 4)Arthur Thomas , Gemstones (2009)
CaWO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references