1 Physical Properties
1.1 Tenacity
1.2 Solubility
Easily soluble in cold dilute HCl
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Brittle, Uneven, Brittle, Uneven
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009)
1.6 Cleavage
Good in two directions parallel to the prism faces {110}
Good in three directions
1.7 Mohs Hardness
1.8 Chemical Composition
CaZn(AsO4)(OH)
K(Ca,Na) 2Si 4O 10(OH,F) · H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references