Green amethyst terminology

A transparent green variety of quartz.

The purple variety of quartz; some suitable material may turn green when treated.

An atomic-scale defect or impurity interaction that can absorb certain wavelengths and create color.

Controlled heating used to change or improve gemstone color.

Exposure to radiation under controlled conditions to alter color centers in a gemstone.

A transparent-looking area in a poorly proportioned cut where light passes through instead of returning to the eye.