UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
Conchoidal, Conchoidal, Gemstones of the world (2001) More from other references, Conchoidal, Brittle
Vitreous, pearly on cleavage
111 (perfect in four directions)
(Fe2+ ,Mg,Mn2+ ) 3(PO 4) 2 · 4H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
C