Polished Marble Bar Chert slab MB131 black jasper 115 mm x 60 mm

115 mm x 60 mm x 40 mm thick

135 mm x 100 mm x 50 mm thick

Weighs 633 grams

Weighs:  235 grams

PRT121  Tumble polished Prehnite from Western Australia

Polished Marble Bar Chert slab MB131 black jasper 115 mm x 60 mmMB131 Marble Bar Chert slab polished on one side . Dimensions at widest points approximately 110 mm x 85 mm x 8 mm thick. Weighs 179 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