White, Colorless, Blue, Red, Green, Yellow, Violet
White, Colorless, Blue, Red, Green, Yellow, Violet
ConchoidalArthur Thomas, Gemstones (2009)
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Tourmaline is a series of several different minerals with unique chemical formulas.
SiO 2Ulrich Henn and Claudio C.