Tenacity
Brittle
-
Solubility
H₂SO₄
-
Durability
-
-
Specific Gravity
2.74-3.002.50-2.80
1
7.18
👆🏻
Fracture
Uneven
-
Cleavage
Distinct on {0001} imperfect on {11 2 0}
Perfect
Mohs Hardness
5-5.55-6.5
2
10
👆🏻
Chemical Composition
Na 4(Ca,Ce) 2(Fe,Mn,Y)ZrSi 8O 22(OH,Cl) 2Ulrich Henn and Claudio C.
Na 4(Al,Si) 12O 24Cl to Ca 4(Si,Al) 12O 24(CO 3,SO 4)Arthur Thomas , Gemstones (2009)