Allende (AMNH 4880)

Part of Hall of Meteorites.

B. Allende hero

A treasure trove of CAIs

This fragment of Allende contains two kinds of calcium-aluminum inclusions (CAIs): round and irregularly shaped. Round CAIs melted and resolidified at some point in their history. Irregularly shaped CAIs, however, never melted: they crystallized directly from the gas of the early solar nebula. The two tons of Allende recovered for study provided scientists with more and larger CAIs than all previously known meteorites combined.