Blue
Colorless, Reddish, White, pink, Green, Yellow, Violet, White, pink, Green, Yellow, Violet, White, Colorless, Blue, Green, Brown, Yellow, pink, Violet, White, pink, Green, Yellow, Violet
Gems, Sixth Edition (2006), Gems, Sixth Edition (2006)
Uneven, UnevenArthur Thomas, Gemstones (2009)
SiO 2Michael OâDonoghue , Gems, Sixth Edition (2006)
KCa 4Si 8O 20(F,OH) · 8H 2OUlrich Henn and Claudio C.