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Some stones show two colors or shades and are called dichroic, some show three and are trichroic. Gems are sometimes cut and set either to display pleochroism or to hide it, depending on the colors and their attractiveness.

Pleochroism is an extremely useful tool in mineralogy for mineral identification, since minerals that are otherwise very similar often have very different pleochroic color schemes. In such cases, a thin section of the mineral is used and examined under transmitted light in a microscope.