Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.55-2.653.07-3.13
1
7.18
👆🏻
Fracture
Conchoidal
Conchoidal, Uneven
Cleavage
Perfect {10 1 0}
{100} Perfect, {010} Distinct, {102} Distinct
Mohs Hardness
5.5-63-3.5
2
10
👆🏻
Chemical Composition
(Na,Ca,K) 8(Si,Al) 12O 24(SO 4,Cl,CO 3) 3(H 2O)Arthur Thomas , Gemstones (2009)
Zn 2(Fe2+ ,Mn2+ )(PO 4) 2 · 4H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references