Conchoidal, ConchoidalAnthony et al, Conchoidal, Brittle, Conchoidal
Uneven, Subconchoidal, Uneven, Subconchoidal, Splintery, UnevenArthur Thomas, Gemstones (2009)
(Zn,Cu)Al 6(PO 4) 4(OH) 8 · 4H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)
Al 2SiO 5Michael OâDonoghue , Gems, Sixth edition (2006) More from other references