Polished Marble Bar Chert slab MB112 axinite Approximate dimensions at widest points

Approximate dimensions at widest points 145 mm  x 75 mm  x 55 mm thick

grinding or polishing as the matrix holding the pisolites (small round pebbles) is in many cases quite soft

DO189  Dendritic Opal slab polished on one side

OJT105  Tumble polished Outback Jasper from Western Australia

Unusual webbing in this piece with small oxidised cubic pyrite inclusions

Polished Marble Bar Chert slab MB112 axinite Approximate dimensions at widest pointsMB112 Marble Bar Chert slab polished on one side . Dimensions at widest points approximately 120 mm x 105 mm x 7 mm thick. Weighs 195 grams. Marble Bar chert is a finely banded, iron rich silica rock from the Marble Bar Chert Member (Warrawoona Group) of Western Australia. Formed in shallow Archean seas, it dates to the Paleoarchean (~3. 46 billion years old), making it one of the Earths oldest well preserved sedimentary rocks. From near the town of