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PO127. Pink porphyry slab, cut and polished on one side.
From Mindoolah, Western Australia.
Dimensions at widest points approximately 195 mm x 120 mm x 9.4 mm thick.
Weighs 469 grams.
Porphyry is a general term that is used rather loosely for igneous rocks which contain relatively large isolated crystals set in a fine-grained groundmass.
The porphyry pictured here has pinkish coloured clinozoisite crystals set in a ground mass of dolerite.
The clinozoisite has replaced but retained the shape of plagioclase feldspar crystals.