Uneven
Conchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Brittle, Metallic
(Fe2+ ,Mg)Al 2(PO 4) 2(OH) 2Michael OâDonoghue , Gems, Sixth Edition (2006)
CaBSiO 4(OH)Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references