Tenacity
-
-
Solubility
-
insoluble
Durability
-
-
Specific Gravity
2.50-2.802.36
1
7.18
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Fracture
-
Uneven, Subconchoidal, Fibrous
Cleavage
Perfect
[110] perfect, [101] good, [010] distinct
Mohs Hardness
5-6.53.5-4
2
10
👆🏻
Chemical Composition
Na 4(Al,Si) 12O 24Cl to Ca 4(Si,Al) 12O 24(CO 3,SO 4)Arthur Thomas , Gemstones (2009)
Al 3(PO 4) 2(OH,F) 3 · 5H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references