Hackly Jagged, torn surfaces, (e.g. fractured metals)., torn surfaces, (e.g. fractured metals).
Subconchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Cu
(Mg,Fe2+ ) 9(SiO 4) 4(F,OH)) 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references