Bridgmanite
Bridgmanite is the most abundant mineral inside Earth, first found in nature in the shocked Tenham meteorite.
Bridgmanite is a magnesium iron silicate with a perovskite crystal structure. Experiments had long suggested it makes up much of Earth's lower mantle, possibly the single most abundant mineral in the planet, yet no natural sample had been found. In 2014 researchers identified it in shock veins in the Tenham L6 chondrite and named it after Percy Bridgman, a pioneer of high-pressure physics.
Bridgmanite needs pressures above roughly 23 gigapascals, equivalent to depths of more than about 660 kilometres inside Earth. In Tenham it formed during an asteroid collision and was frozen in place as the shock vein cooled within seconds.
The discovery shows how meteorites can supply natural examples of materials that otherwise exist only deep within planets. Bridgmanite in meteorites also gives a lower limit on the pressures reached when asteroids collided, helping model how the parent bodies of chondrites were broken up.
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