Yellow, White, Brown, Brownish, Black
White, Colorless, Blue, Red, Green, Yellow, Violet
Sub-Conchoidal, ConchoidalArthur Thomas, Conchoidal, Uneven
Not Available
(Fe,Mn)AlPO 4(OH) 2 -H 2OArthur Thomas , Gemstones (2009)
SiO 2Ulrich Henn and Claudio C.