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Fireworks. Jellyfish. Galaxies. Lightning. Opal’s shifting play of kaleidoscopic colors is unlike any other gem.

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Most opals are cut as cabochons; this one from Ethiopia weighs 20.86 ct.

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Unique Beauty

The play-of-color displays the entire spectrum over a light gray background.

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Bright flashes of color skip across this stone’s surface.

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Hidden Beauty

Opal forms as irregular nodules or seams in volcanic or sedimentary rocks.

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Rare Phenomena

Play-of-color results when light interacts with orderly stacks of spheres.

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This opal nodule displays the promise of intense play-of-color.

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Photos & Videos

An 18K yellow gold “Gold Rush” bracelet features garnet, carnelian, citrine, tourmaline, blue topaz, iolite and amethyst. Photo by Sandra Stampfli, courtesy Bahina Jewels
Open-pit mine
Man holding opal
All photos remain under the ©Gemological Institute of America copyright and may only be used with permission. More Copyright Information