12021 (134) - Pigeonite basalt
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Fact sheet
Description: 

12021 is a coarse-grained porphyritic pigeonite basalt that has been dated at 3.3 b.y. old. It has been described as a porphyritic basalt with elongate pyroxene phenocrysts up to 2 cm in length set in a variolitic groundmass of pyroxene, plagioclase and ilmenite. Groundmass includes silica phases, pyroxferroite, metallic iron, and glass. A striking feature is the presence of large anhedral pyroxene phenocrysts up to 10 mm long. No olivine was observed. The texture of 12021 is intrafasciculate - used to describe the hollow cores of elongate plagioclase and pyroxene needles in this rock.

The sample weighed 1876.2 grams before analysis.

Further details of this and other Apollo samples are here: http://curator.jsc.nasa.gov/lunar/

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Not known
Ma = Millions of years ago
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igneous
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