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| Click on image to enlarge. Photo © Daniel R. Snyder |
Epidote in greenschist. In XPL image above, epidote grains are yellow to orange to magenta; some of them, at or near extinction, are dark brown or black. Many of the larger grains show epidote's characteristic oval shape. Small, irregularly-shaped epidote grains in the upper half of the image are partially masked by their high-relief outlines, and also by magnetite grains and finely disseminated magnetite. Imaged area 0.57 mm x 0.8 mm.
The two PPL images below cover the same area as the XPL image above. The characteristic yellow-green to green pleochroism of epidote is evident in these images, which were made with the polarizer at two different angles, approximately 90 degrees apart. Many magnetite grains, clustered above the center of the image and in the upper right corner, are more clearly visible in these PPL images than in XPL.
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| Click on image to enlarge. Photo © Daniel R. Snyder |
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| Click on image to enlarge. Photo © Daniel R. Snyder |
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