Pebble of andesite, an extrusive volcanic (igneous) rock with a typical porphyritic texture, being that of twinned crystals of feldspar (white) floati

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Pebble of andesite, an extrusive volcanic (igneous) rock with a typical porphyritic texture, being that of twinned crystals of feldspar (white) floating in an amorphous matrix of solid lava, here of brick-red colour. This porphyritic texture is caused by exsolution, a process of separation that takes place during successive phases of crystallisation and solidification in the lava. Pebble's actual width is 100 mm.

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Size: 5616px × 3744px
Photo credit: © DIRK WIERSMA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: andesite, brick, crystal, crystalline, crystals, earth, exsolution, extrusive, feldspar, geological, geology, igneous, lava, mineral, mineralogy, phenocryst, phenocrysts, porphyritic, red, rock, science, separation, texture, typical, volcanic