Tenacity
Brittle
Brittle
Solubility
H₂SO₄
-
Durability
-
-
Specific Gravity
2.74-3.003.69-3.81
1
7.18
👆🏻
Fracture
Uneven
Uneven, Conchoidal to uneven, ConchoidalWalter Schumann
Cleavage
Distinct on {0001} imperfect on {11 2 0}
Distinct on {110}, imperfect on {010}, poor on {001}
Mohs Hardness
5-5.58.5
2
10
👆🏻
Chemical Composition
Na 4(Ca,Ce) 2(Fe,Mn,Y)ZrSi 8O 22(OH,Cl) 2Ulrich Henn and Claudio C.
BeAl 2 O 4