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| Click on image to enlarge. Photo © Daniel R. Snyder |
Optical scan of rough-polished section of fine-grained greenstone cobble. Throughout the specimen, larger grains enclose numerous smaller grains: poikiloblastic texture. Cobble from glacial gravel in southeastern Michigan, provenance likely northern Ontario. Imaged area 6.35 cm by 8.67 cm.
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| Click on image to enlarge. Photo © Daniel R. Snyder |
Higher-magnification view of an area near the center of the previous image, clearly showing the inclusions in almost all of the larger grains. Imaged area 10 mm by 17 mm.
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| Click on image to enlarge. Photo © Daniel R. Snyder |
Image illustrating the small grain size typical of this greenstone specimen. Enlarge this image to see the smaller individual grains in the darker areas. XPL, 10X objective. Imaged area 0.5 mm by 0.8 mm.
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| Click on image to enlarge. Photo © Daniel R. Snyder |
A plagioclase lath (center ) has been almost entirely replaced by epidote. XPL, 10X objective. Imaged area 0.5 mm by 0.8 mm.
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| Click on image to enlarge. Photo © Daniel R. Snyder |
As above, PPL. Epidote is indicated by high-relief green areas.
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