BJ142 Polished "Black Jade" slab. Opalite Dimensions at widest points approximately

Dimensions at widest points approximately 120 mm x 80 mm x 20 mm thick

120 mm x 70 mm x 35 mm

It probably grew in shallow water conditions with intermittent subaerial exposure

Weighs 809 grams

Dimensions approximately 130 mm x 120 mm x 90 mm thick

BJ142 Polished "Black Jade" slab. Opalite Dimensions at widest points approximatelyBJ142 Polished "Black Jade" A trade name for metamorphosed magnesian tholeiite (basalt). A slab, cut and polished on one side . Difficult to photograph due to the mirror black polish.. Dimensions at widest points approximately 145 mm x 40 mm x 7 9 mm thick. It weighs 134 grams. From our mining lease on Ninghan Station in the Midwest region of Western Australia.