Tenacity
Tough
-
Solubility
-
insoluble
Durability
-
-
Specific Gravity
2.78-2.852.36
1
7.18
👆🏻
Fracture
Uneven
Uneven, Subconchoidal, Fibrous
Cleavage
Perfect basal (001)
[110] perfect, [101] good, [010] distinct
Mohs Hardness
2-2.53.5-4
2
10
👆🏻
Chemical Composition
KMg3(Si3Al)O10(F,OH)2
Al 3(PO 4) 2(OH,F) 3 · 5H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references