Two materials, lonsdaleite and wurtzite, have just been recognized as being harder than diamonds. Lonsdalite, similar to diamonds that its made from carbon, is formed during asteroid impacts, and is 58% harder than its cousin. Wurtzite boron nitride is formed during heavy volcanic eruptions and can be up to 18% harder than diamonds. oth are exceedingly rare in nature, and both form under crushing, searing conditions. Lonsdaleite is a cousin of the diamond, a hexagonal arrangement of carbon atoms that’s 58% stronger than its shimmering relative, according to a computer simulation of its behavior

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Discovered Materials Formed In Asteroid Impacts and Volcanic Eruptions Much Harder Than Diamonds [Diamonds]