Staurolite crystal. Polarised light micrograph of a large staurolite crystal, also known as a porphyroblast, embedded in a micaceous matrix. This crys

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Staurolite crystal. Polarised light micrograph of a large staurolite crystal, also known as a porphyroblast, embedded in a micaceous matrix. This crystal was formed later than the host rock itself. After its formation, the staurolite crystal reacted with its surrounding host rock to form a conversion ring of biotite crystals around its periphery. This image has been obtained using cross-polarised light (or 'crossed nichols').

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Size: 4759px × 3768px
Photo credit: © DIRK WIERSMA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: biotite, conversion, cross, cross-polarised, cross-polarized, crossed, crystal, crystalline, crystals, earth, geological, geology, host, light, lm, matrix, micaceous, micrograph, microscope, microscopy, mineral, mineralogy, minerals, nichols, plm, polarised, polarized, porphyroblast, ring, rock, rocks, science, section, sectioned, staurolite