Round lime-green peridot gemstone on a black background

Peridots

Born of Fire — the Sunlit Green of Earth's Deep Mantle

Peridot is the gem variety of olivine, and one of the very few gems whose color comes from its own essential chemistry rather than trace impurities — iron is part of the formula, so peridot is always green, and it is never treated. It is also one of only two gems (with diamond) formed not in the Earth's crust but in the mantle, carried to the surface by volcanoes.

The ancient Egyptians mined it on the Red Sea island of Zabargad 3,500 years ago and called it the “gem of the sun.” Today its sunlit lime-to-olive greens make it a fresh, confident choice — and the birthstone of August.

How Peridots Are Formed

Open-pit gemstone mine with tiered stone layers and excavation vehicles

Peridot crystallizes in peridotite rock of the upper mantle, twenty to fifty-five miles below the surface. Basaltic eruptions tear off nodules of that mantle rock and carry them upward — most of the world's peridot literally rode a volcano to reach us.

Because iron is part of olivine's essential chemistry, peridot is idiochromatic: it can only be green. Lower iron gives brighter lime tones; more iron pulls toward olive and brown. Traces of chromium and nickel brighten the very best stones.

The finest large crystals come from pockets high in Pakistan's Himalaya at Suppat, with Myanmar a historic rival. Arizona's San Carlos Reservation supplies the market's everyday stones — and a few peridots have even arrived inside pallasite meteorites, older than the Earth's surface itself.

What Makes a Peridot Valuable?

Value is determined by several universal factors:

Color

The finest peridot is a pure, saturated grass-green without brown — the standard set by Pakistani and Burmese stones. Bright “apple” lime-greens are prized; olive and brownish tones are the commercial norm.

Clarity

Eye-clean stones are expected. Tiny disc-like “lily pad” inclusions are a characteristic signature; prominent black spots discount value.

Cut

Peridot's strong birefringence can double back facets visually, so skilled cutters orient the stone to keep the view crisp. Ovals, cushions, and brilliant styles wake up the green.

Carat Weight

Small Arizona stones keep everyday peridot accessible. Fine, saturated stones above five carats — Pakistani or Burmese — are genuine collector pieces.

Origin

Suppat in Pakistan sets the modern standard, Myanmar supplies large fine gems, and Arizona's San Carlos fields anchor the commercial market. Egypt's Zabargad is the storied ancient source.

Treatment

Peridot is not treated — its color is built into its chemistry. What you see is exactly what formed in the mantle.