Polished Porphyry . PO 122 alcheringa narrina GREEN76 Green Opal & Magnesite

GREEN76  Green Opal & Magnesite rough rock

Dimensions approximately 170mm x 45mm x 15-45mm thick

Ord Ranges near Port Hedland

It weighs 10

Dimensions at widest points approximately 130 mm x 65 mm x 9 mm thick

Polished Porphyry . PO 122 alcheringa narrina GREEN76 Green Opal & MagnesitePO122. Pink porphyry slab, cut and polished on one side. From Mindoolah, Western Australia. Dimensions at widest points approximately 290 mm x 165 mm x 10 mm thick. Weighs 898 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