Glossary entry

Prasiolite

Definition
A transparent green variety of macrocrystalline quartz, commonly produced commercially by heat-treating amethyst or irradiating quartz.

Why it matters

Prasiolite is the clearest gemological name for the material frequently sold as “green amethyst.” The term helps distinguish green quartz from purple amethyst and from unrelated green gemstones.

Examples

Faceted prasiolite is used in rings, pendants, earrings, and loose-stone collections. It often appears pale mint, yellow-green, gray-green, or leek green.

Related terms

Amethyst, quartz, heat treatment, irradiation, green quartz, color center, windowing.

Research links

Prasiolite treatments · What is green amethyst?