Silicate aggregates, including large single crystals of potassium feldspar as long as 11 centimeters and sodium feldspar, are embeded in the surface of the medium octahedrite Colomera. Silicate nodules in the interior appear to be much smaller (about 0.3 centimeter). Glass nodules are abundant both on the external surface and in the interior. These observations are evidence that some iron meteorites formed as segregations within a silicate matrix and did not originate in a metallic core.
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Machine-learning crystal size distribution for volcanic stratigraphy correlation.
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