ConchoidalGemdat.org, Management Team (2012), ConchoidalGemdat.org, Management Team (2012)
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Not Available
(Ca,Mn2+ )Si 3O 9Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references