Subconchoidal, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Uneven
{0001} good, {10 1 0} parting
{100} Perfect, {010} Distinct, {102} Distinct
(Ca,Ce)(Al,Ti,Mg)12O19
Zn 2(Fe2+ ,Mn2+ )(PO 4) 2 · 4H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references