Clan
A clan is a set of meteorite groups that share important features and probably formed in neighbouring regions.
A clan sits between a class and a group in meteorite classification. It links groups that are chemically, mineralogically and isotopically related but differ enough in detail to remain separate, perhaps because they came from separate parent bodies formed close together in the disc.
The best-known example is the CR clan, which joins CR, CH and CB chondrites. All three are metal-rich and share oxygen and nitrogen isotope features. Another is the CM–CO clan, whose groups have similar refractory inclusions and oxygen isotopes but different degrees of water alteration. CV and CK chondrites have also been suggested as a clan, and some researchers even argue they come from one body.
The idea helps organise the growing number of meteorite types. It suggests that the early Solar System contained neighbourhoods of related asteroids, each making slightly different versions of a basic recipe.
Related terms
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