Polished Tiger Iron slab TI275 #gemstone Porphyry is a general term

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

Dimensions at widest points approximately 155 mm x 150 mm x 50 mm thick

120 mm x 85 mm x 50 mm

Dimensions approximately 50mm x 85mm x 7mm thick

Dimensions at widest points approximately 80 mm x 60 mm x 40 mm thick

Polished Tiger Iron slab TI275 #gemstone Porphyry is a general termTI275 Tiger Iron slab, polished on one side . Dimensions at widest points approximately 120 mm x 95 mm wide x 8 mm thick. Weighs: 235 grams From the Cleaverville Formation, Ord Ranges near Port Hedland, Western Australia. Age is over 3 billion years. , Tiger iron is a banded iron formation (BIF) or jaspilite that has alternating layers of black and brown hematite magnetite, red jasper and chatoyant golden tiger eye.