UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Conchoidal, ConchoidalAnthony et al, Conchoidal, Brittle, Conchoidal
BaCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
(Zn,Cu)Al 6(PO 4) 4(OH) 8 · 4H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)