Not Available
Afghanistan, Pakistan, Burma, Brazil, Madagascar, USA, Canada, Russia, Madagascar, Brazil, Canada, Mexico, Madagascar, Brazil, Canada, Mexico
Sub-Conchoidal, Brittle, Metallic
Gemstones of the world (2001), UnevenWalter Schumann, Gemstones of the world (2001)
Visible X=Y= canary yellow to greenish yellow
Strong trichroism: colorless pink violetHerve Nicolas Lazzarelli