Abstract:

The different crystal structures and chemical compositions in tourmalines with color zonings account for the inhomogeneous physical characters of these tourmalines. EMPA, IR and Raman spectrometers were used to detect four groups of tourmalines and crystal structures and chemical compositions of these crystals were discussed. The chemical compositions of these tourmalines indicated that the amount of TFe and TMn are greatly connected with the color causes of tourmalines. Four groups of tourmalines were assigned to Li-tourmalines because of the chemical compositions and characters of infrared spectra. The chemical composition also can tell us that the amount of SiO₂  cause the shifts of Si-O and [Si₆O₁₈]^12-.

Key words: tourmaline, color genesis, transitional ions, infrared spectra, Raman spectra, Xinjiang