Polished Marble Bar Chert slab MB113 crystophase OJ204 A slab

OJ204  A slab

Weighs 764 grams

TIR164 Tiger Iron rough rock

Dimensions at widest points approximately 235 mm x 200 mm and 175 mm thick

All reasonably uniform in size (roughly 20 -30 mm diameter}

Polished Marble Bar Chert slab MB113 crystophase OJ204 A slabMB113 Marble Bar Chert slab polished on one side . Dimensions at widest points approximately 100 mm x 80 mm x 8. 5 mm thick. Weighs 156 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