The refractive indices of the 20 amethyst samples from Boudi varied from 1.540 to 1.542 (o-ray) and 1.549 to 1.552 (e-ray), with birefringence from 0.009 to 0.010. Pleochroism, observed with a calcite dichroscope, varied from weak to medium bluish purple to reddish purple. None of the samples showed any reaction to either short- or long-wave UV radiation. No absorption spectra were observed using the Krüss spectroscope.