Last updated: November 28, 2021 at 10:28 PM
The birthstones of November are topaz and citrine. Topaz is a common color with champagne color. Blue topaz also has natural color, but the distribution volume is negligible. Most of the blue topaz is treated to colored stones such as "Swiss blue" and "London blue" by gamma-ray irradiation and heat treatment. Natural stones also exist in citrine (yellow crystal), but there are also stones in which amethyst (purple crystal) is heat-treated and discolored yellow. The pendant in the photograph seems to be the treated stone.
