Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
2.60-2.642.79-2.87
1
7.18
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Fracture
Uneven, Splintery, Conchoidal
Conchoidal
Cleavage
Absent
{010} perfect; {100} good, interrupted; {101} indistinct; {001} in traces
Mohs Hardness
6.5-75.5-6
2
10
👆🏻
Chemical Composition
SiO 2Arthur Thomas , Gemstones (2009)
NaBePO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references