Tenacity
-
Brittle
Solubility
-
H₂SO₄
Durability
-
-
Specific Gravity
2.55-2.652.74-3.00
1
7.18
👆🏻
Fracture
Conchoidal
Uneven
Cleavage
Perfect {10 1 0}
Distinct on {0001} imperfect on {11 2 0}
Mohs Hardness
5.5-65-5.5
2
10
👆🏻
Chemical Composition
(Na,Ca,K) 8(Si,Al) 12O 24(SO 4,Cl,CO 3) 3(H 2O)Arthur Thomas , Gemstones (2009)
Na 4(Ca,Ce) 2(Fe,Mn,Y)ZrSi 8O 22(OH,Cl) 2Ulrich Henn and Claudio C.