Meteorites are of three kinds: stones, irons, and stony irons. Each corresponds to a different part of planet formation. The stones resemble pieces of planetary crust and mantle, the irons the planet cores, and the stony irons the transitional area between core and mantle. In some stony irons, translucent crystalline structures interpenetrate with opaque mantle rock. Collectors sometimes cut stony irons into thin slices and illuminate them from one side for a gorgeous stained-glass effect. Only one per cent of all meteorites are stony irons. Five per cent are irons, and the remaining ninety-four per cent are stones.
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