Southern and central Africa
USA, Southern and central Africa, green, blue, China, India, USA, Italy, green, blue, China, India, USA, Italy
Yellow, Green, Blue, Violet
White, Yellow
Al 2O 3Ulrich Henn and Claudio C.
H 4Mg 3Si 2O 9Walter Schumann , Gemstones of the world (2001) More from other references