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Wasdale Old Bridge, Shap Rural, Orton S, Cumbria, NY56470835 -- Rock, hand specimen of a igneous rock, Shap granite, a porphyry, from the streambed at Wasdale Old Bridge, Shap Rural, Westmorland, NY56470835, 24 August 2012.
Lower Devonian.
The grey crystals are quartz; silcon dioxide, Si02.
The white crystals are feldspars; sodium aluminium silicate, NaAlSi3O8, or potassium aluminium silicate, KAlSi3O8, or calcium aluminium silicate, CaAl2Si2O3.
The black crystals are biotie or perhaps hornblende, complicated lattice silicates.
This is a porphyry; the larger pink crystals are orthoclase feldspar; these phenocrysts indicate a very slow cooling of the igneous intrusion.
(photo 24.8.2008)