Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
3.65-4.552.25-2.40
1
7.18
👆🏻
Fracture
Conchoidal
-
Cleavage
None, but may exhibit slight parting
perfect on {010}; good on {100}
Mohs Hardness
7.5-85-5.5
2
10
👆🏻
Chemical Composition
(Mg,Zn)Al 2O 4Gemdat.org , Management Team (2012)
NaCa 2Al 5Si 5O 20 · 6H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references