Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle
Perfect on [10 1 1] three directions with angle of 74° 55
Imperfect, poor one {100}
CaCO 3Ulrich Henn and Claudio C.
Zn 2(AsO 4)(OH) · H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references