TED-Ed

The most colorful gemstones on Earth - Jeff Dekofsky (2020x136)

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In November 1986, Australian miners climbed Lunatic Hill and bored 20 meters into the Earth. They were rewarded with a fist-sized, record breaking gemstone, which they named the Hailey’s Comet opal. Thanks to a characteristic called “play of color,” no two opals look the same. So what causes these vibrant displays? Jeff Dekofsky digs into the rock’s shimmering, dancing displays of light. Lesson by Jeff Dekofsky, directed by Ivana Bošnjak and Thomas Johnson.