UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Brittle, Metallic
Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Mn2+ Zn 2SiO 4(OH) 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
CaCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references