What are the gems that show dichroism?

First of all, understand what is the dichroism of gemstones.

Dichroism of gems refers to the anisotropy of anisotropic gems, which leads to different directions of gems and different absorption of light, resulting in different colors of gems.

For example, corundum, except colorless corundum, all colored corundum gems have dichroism.

Common red corundum gems have dichroism in different directions, such as deep red-light red, red orange red, purple red-brown red and so on.

The dichroism of blue corundum gemstones in different directions includes dark blue-light blue, blue-turquoise, blue-gray blue and so on.

Tourmaline also has medium to strong dichroism, including light green-dark green, dark green-dark green and so on.

Besides corundum and tourmaline, there are also emeralds and aquamarine.