The Color of
of Geological and Planetary Sciences,
California Institute of Technology, Pasadena, CA 91125
when of the ideal composition (free of minor impurities and free from
exposure to natural or laboratory irradiation) would be colorless.
Topaz also occurs in a variety of colors ranging through yellow,
orange, brown, pink, violet, and blue. Unlike many other minerals, most
of the colors of topaz, with the exception of pink, are the result of
irradiation, either natural or laboratory. Determination of the atomic
level origin of the irradiation colors is difficult; conflicting
interpretations remain to this day.
Irradiated greenish topaz
last updated 07-Aug-2011