Tenacity
Brittle
Brittle
Solubility
H₂SO₄
-
Durability
-
-
Specific Gravity
2.74-3.002.33-2.37
1
7.18
👆🏻
Fracture
Uneven
ConchoidalWalter Schumann
Cleavage
Distinct on {0001} imperfect on {11 2 0}
Perfect on {010}, good on {100}
Mohs Hardness
5-5.57.5
2
10
👆🏻
Chemical Composition
Na 4(Ca,Ce) 2(Fe,Mn,Y)ZrSi 8O 22(OH,Cl) 2Ulrich Henn and Claudio C.
Be 2BO 3(OH)Ulrich Henn and Claudio C.