ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Sub-Conchoidal, ConchoidalArthur Thomas, Conchoidal, Uneven
NaAl 3(PO 4) 2(OH) 4 · 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
(Fe,Mn)AlPO 4(OH) 2 -H 2OArthur Thomas , Gemstones (2009)