Diogenite stone meteorite from Asteroid Vesta. Northwest Africa, found 2013. Complete laboratory-prepared slice. Weighing 19.9 grams and measuring 73 mm x 44 mm x 3 mm. Diogenites could just be one of the most fascinating rock types in existence and they are thought to be of plutonic origin. In both terrestrial and extraterrestrial geology, plutonic rocks are intrusive igneous rocks. That means they were once lava, but instead of being thrown out by a volcano and cooling on the surface, they cooled slowly underground. Slow cooling means they had time to grow large crystals which are often green in color.
Diogenites take their name from the Greek philosopher Diogenes of Apollonia. Diogenes lived in the Fifth Century B.C.E. in Thrace and in Athens and he believed that the universe was a constant, vast living substance and that our atmosphere was part of it and intelligent and, as such, was the source of all being. Sherlock Holmes fans will remember that Sherlock’s mysterious older brother, Mycroft, was co-founder of an equally mysterious gentleman’s association called The Diogenes Club. Accompanied by a certificate of authenticity from Aerolite Meteorites.
The other Vesta meteorite types—howardites and eucrites—journeyed to Earth from that giant asteroid’s surface, but diogenites are different. They originated deep underground and were delivered here because of the catastrophic meteorite impacts that occurred on Vesta in the distant past. Diogenites are cooled crystalline magma (or lava), excavated from deep inside Vesta by a meteorite impact so tremendous, it blasted right through the crust to the interior of our largest asteroid. The excavated material was expelled into space and some of it eventually landed on Earth as diogenite meteorites. Only a single stone of NWA 11342 was found in Morocco in 2017, and this complete laboratory-prepared slice was taken from it. NWA 11342 was examined and classified by the Institute of Meteoritics in Albuquerque, NM and the type specimen remains in their permanent collection.
Terms and abbreviations used in our descriptions.