Rock 366 : Day 52 : Andalusite-biotite Hornfels

Rock3660183

Day 52 : An andalucite-biotite hornfels in the aureole of the Ardara pluton, Donegal, Ireland. Andalucite porphyroblasts are more concentrated in clay (bottom) rather silt layers. Keele collection. 

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~ by hypocentre on February 21, 2012.

 
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