Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
1.792.9-3.5
1
7.18
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Fracture
Irregular/uneven
Conchoidal
Cleavage
Perfect on {10bar10}
{110} Perfect, {???} Distinct, {???} Distinct
Mohs Hardness
2.55.5-6
2
10
👆🏻
Chemical Composition
Ca6(Al,Si)2(SO4)2B(OH)4(OH,O)12•26(H2O)
(Mg,Fe2+ ) 2(Mg,Fe2+ ) 5Si 8O 22(OH) 2Anthony et al , Handbook of mineralogy (2001)