Southern and central Africa
USA, Southern and central Africa, green, blue, China, India, USA, Italy, green, blue, China, India, USA, Italy
ConchoidalWalter Schumann, Gemstones of the world (2001), ConchoidalWalter Schumann, Gemstones of the world (2001)
Uneven, Uneven, Gemstones of the world (2001) More from other references
SiO 2 · nH 2OWalter Schumann , Gemstones of the world (2001)
H 4Mg 3Si 2O 9Walter Schumann , Gemstones of the world (2001) More from other references