Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
1.97-2.223.1-3.2
1
7.18
👆🏻
Fracture
Conchoidal
-
Cleavage
None
Vitreous, pearly on cleavage
Mohs Hardness
6-6.53-4
2
10
👆🏻
Chemical Composition
SiO 2 · nH 2OWalter Schumann , Gemstones of the world (2001) More from other references
(Fe2+ ,Mg,Mn2+ ) 3(PO 4) 2 · 4H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references