1 Physical Properties
1.1 Tenacity
1.4 Solubility
1.7 Durability
Not Available
Not Available
1.9 Specific Gravity
1.17 Fracture
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001)
Uneven, UnevenArthur Thomas, Gemstones (2009), Conchoidal, Brittle
1.18 Cleavage
{???} Good, {???} Good
Imperfect on {110}
1.19 Mohs Hardness
1.20 Chemical Composition
(Ca,Mn2+ ,Fe2+ ) 3Al 2BSi 4O 15(OH)Anthony et al , Handbook of mineralogy (2001)
(Na,Ca) 8Al 6Si 6O 24(SO 4,S,Cl) 2Ulrich Henn and Claudio C.