Sub-Conchoidal, Irregular/uneven, Sub-Conchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001)
(Li,Na)Al(PO 4)(F,OH)Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
NaFe3+3Fe3+6(BO 3) 3Si 6O 18(O,OH) 4Anthony et al , Handbook of Mineralogy (2001)