corundum, Tanzania.12, gems

Describes rubies, blue sapphires and other colored corundums from Tanzania, with particular attention to their gemological characteristics. The authors characterize the colors quantitatively using a chromaticity-coordinate diagram and examine the stones’ absorption spectra and mineral inclusions. The study compares the different color varieties and relates their optical behavior to their composition, providing analytical data useful for characterizing Tanzanian gem corundum. A contemporary Journal of Gemmology abstract specifically notes the treatment of color, inclusions and absorption spectra.