Uneven, Subconchoidal, Uneven, Subconchoidal, Splintery, UnevenArthur Thomas, Gemstones (2009)
Subconchoidal, Uneven, Conchoidal, Uneven
Al 2SiO 5Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
Mn2+ Al(PO 4)(OH) 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)