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Prasiolite

Prasiolite is a mineral (SiO₂) with a Mohs hardness of 7 and a vitreous luster, usually green.

Green quartz. Natural pieces are uncommon; nearly all prasiolite for sale is amethyst that has been heated, or yellow quartz that has been irradiated.

Prasiolite specimen
Photo: Mauro Cateb, CC BY-SA 4.0, via Wikimedia Commons

How to identify prasiolite

  • Even leek-green to olive, not banded like aventurine.
  • Hardness 7, with quartz's curved fracture.
  • Heated amethyst often keeps a geode shape with paler bases.

Often confused with

Where it's found

  • Lower Silesia, Poland
  • Bahia, Brazil
  • Thunder Bay, Ontario
  • Namibia

Uses

Gemstones.

Rock tumbling

Great for tumbling.

Did you know?

Most amethyst turns yellow or orange when heated and is sold as citrine. Amethyst from only some localities turns green instead, which is how nearly all commercial prasiolite is made.

Prasiolite FAQ

What is prasiolite?

Prasiolite is a mineral (SiO₂) with a Mohs hardness of 7 and a vitreous luster, usually green. Green quartz. Natural pieces are uncommon; nearly all prasiolite for sale is amethyst that has been heated, or yellow quartz that has been irradiated.

How do you identify prasiolite?

Even leek-green to olive, not banded like aventurine. Hardness 7, with quartz's curved fracture. Heated amethyst often keeps a geode shape with paler bases.

How hard is prasiolite?

Prasiolite has a Mohs hardness of 7. Prasiolite scratches glass, and a steel knife can't scratch it.

Where is prasiolite found?

Notable localities include Lower Silesia, Poland; Bahia, Brazil; Thunder Bay, Ontario; and Namibia.

What is prasiolite used for?

Gemstones.

Can you tumble prasiolite?

Yes — it tumbles well.

What is prasiolite often confused with?

Prasiolite is most often confused with Olivine, Hiddenite and Aventurine. Peridot is heavier, grainier and a brighter bottle green. Hiddenite is spodumene: it cleaves and is slightly softer. Aventurine sparkles from mica flakes; prasiolite is even-colored quartz.

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