Akimotoite
Akimotoite is a very dense high-pressure form of pyroxene chemistry discovered in a shocked meteorite.
Akimotoite is a magnesium silicate with an ilmenite-like crystal structure. It forms from pyroxene at very high pressures and was first identified in nature in 1999 in the Tenham L6 chondrite, which fell in Australia in 1879. It is named after the Japanese mineral physicist Syun-iti Akimoto.
In meteorites, akimotoite appears inside the shock veins of strongly shocked chondrites, typically as tiny grains formed in the hottest, highest-pressure zones. Its stability requires pressures above about 20 gigapascals, so finding it sets a minimum on how hard the parent asteroid was hit.
Scientists believe akimotoite may exist in parts of Earth's deep mantle, near the boundary at 660 kilometres. Because samples from such depths are unreachable, minerals created naturally in shocked meteorites give researchers real crystals to compare with laboratory experiments.
Related terms
Level: Expert Advanced