Diogenite Meteorite | From The Asteroid Vesta — Partial Slice Of The Diogenite NWA 7831

Diogenites originate from the asteroid Vesta — the only known asteroid which, like Earth, contains a molten iron core, stony mantle and crust. The delivery mechanism to Earth was the ejection of material following a massive collision with another asteroid billions of years ago. A massive “scar” from this impact on Vesta is readily identifiable. Diogenites are plutonic rocks (they originated from magma that was not expelled to the surface but which slowly cooled deep underground enabling the development of large crystals). We know diogenites originate from Vesta largely as a result of NASA’s Dawn space probe which orbited Vesta in 2011 and 2012 during which time reams of data was transmitted to researchers.

This partial slice is evocative of a pallasite (see lots 93, 98, 103) but without metal. The crystals seen here are of the silicate orthopyroxene. Almost all of NWA 7831 (the 7,831^st meteorite to be recovered and analyzed following its recovery from the North West African grid of the Sahara Desert) is yellow-green orthopyroxene — a most unusual presentation. In addition to oxygen isotopes, grains of other minerals confirm its extraterrestrial origin. From the only asteroid that can be seen with the naked eye, and the furthest place from Earth in which samples on Earth are known to exist, this is an enthralling partial slice of an exotic diogenite.