Scanning electron micrograph (SEM) of iron crystals growing in a small vug, or cavity, in a recrystallized breccia (fragmented rock) from the Apollo 1

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Scanning electron micrograph (SEM) of iron crystals growing in a small vug, or cavity, in a recrystallized breccia (fragmented rock) from the Apollo 15 Hadley-Apennine lunar landing site. The largest crystal is three micrometres across. Perfectly developed crystals such as these indicate slow formation from a hot vapour as the rock was cooling. The crystals are resting on an interlocking lattice of pyroxene (calcium-magnesium-iron silicate).

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Size: 3300px × 3762px
Photo credit: © NASA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: -, 15, apollo, astrogeology, astronomical, astronomy, black, crystal, exogeology, growth, hadley-apennine, iron, lunar, monochrome, moon, nasa, program, pyroxene, sample, sem, white