Sub-Conchoidal, ConchoidalArthur Thomas, Conchoidal, Uneven
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Uneven
(Fe,Mn)AlPO 4(OH) 2 -H 2OArthur Thomas , Gemstones (2009)
Mn 3B 7O 13ClMichael OâDonoghue , Gems, Sixth Edition (2006)