Meteorite classification and the definition of new chondrite classes as a result of successful meteorite search in hot and cold deserts

Meteorites are classified in order to sort these extraterrestrial rocks into broadly similar types of objects to enable a better understanding of the origin of these rocks and their relationships. Considering their origin and evolution, meteorites are broadly subdivided into two main divisions “differentiated” and “undifferentiated” meteorites. Successful meteorite searches in hot and cold deserts have drastically increased the number of meteorite finds. More than 20 000 meteorite fragments have been recovered mainly by Japanese and American expeditions from Antarctica. The number of collected meteorites from hot deserts is estimated to be about 7000–8000 including several 10 000 of fragments. Many rare samples are among the new meteorite finds leading to the definition of new meteorite classes and groups. These are R chondrites, CK, CR, and CH chondrites, acapulcoites, winonaites, lodranites, brachinites, angrites, and Lunar meteorites.