Day #118 Deskcrop: Staurolite Schist (Thin Section)

Today’s thin section “deskcrop” revisits the Black Hills staurolite schist featured back on March 24th. And those honkin’ big staurolite porphyroblasts don’t just look good in hand sample! In the thin sections below you’ll note the distinctly poikiloblastic texture of both the large staurolite porphyroblasts and the somewhat smaller garnet porphyroblasts, as well. You may also not the pleochroism displayed by both the staurolite and biotite crystals going from the first to the third images below. Um wa!

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Zoomed-out, Plane Light

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Zoomed-out, X-polars

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Zoomed-out, Rotated, Plane Light

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Zoomed-out, Rotated, X-polars

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Zoomed-in, Plane Light

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Zoomed-in, X-polars

Explore this and all of my 2010 Deskcrops and Outcrops in Google Earth!