Butler, missouri: an unusual iron meteorite.
The Butler iron meteorite has been found to have, with respect to other iron meteorites, an unusually high cobalt content (1.4 percent by weight), unusually high germanium contents in the kamacite and the taenite phases, and an unusually low cooling rate (0.5 degrees C/10(6) years). It is suggested that Butler formed in a different environment from that of the rest of the iron meteorites.
Goldstein
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