Tenacity
Very brittle
-
Solubility
insoluble
-
Durability
-
-
Specific Gravity
3.30-3.403.1-3.2
1
7.18
👆🏻
Fracture
Conchoidal
-
Cleavage
{010} perfect, {110} distinct, {100} in traces
Vitreous, pearly on cleavage
Mohs Hardness
6.5-73-4
2
10
👆🏻
Chemical Composition
AlO(OH)Walter 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