1 Physical Properties
1.1 Tenacity
1.2 Solubility
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
2.54-2.782.20-2.23
1
7.18
1.5 Fracture
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009)
Irregular/uneven, UnevenAnthony et al, Handbook of mineralogy (2001), Brittle, Uneven
1.6 Cleavage
Good in three directions
Perfect on {110} and {1 1 0}
1.7 Mohs Hardness
1.8 Chemical Composition
K(Ca,Na) 2Si 4O 10(OH,F) · H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
CaAl 2Si 3O 10 · 3H 2OUlrich Henn and Claudio C.