Polished Green Opal rock GRN102 mookaite A domal stromatolite from the

A domal stromatolite from the Proterozoic "Irregully Formation" in Western Australia

Dimensions approximately 170mm x 100mm x 7mm thick

RH257  A slab

Dimensions at widest points are approximately 65 mm x 45 mm x 35 mm

Dimensions at widest point approximately 80 mm x 70 mm x 8

Polished Green Opal rock GRN102 mookaite A domal stromatolite from theGRN102 Green Opal & Magnesite rough rock, cut and polished on one side with a rough, naturally weathered back Dimensions at widest points approximately 90 mm x 50 mm x 40 mm thick Weighs 340 grams Green Opal occurs at a location south of Kalgoorlie in the Eastern Goldfields of Western Australia. The green colouration is caused by traces of nickel and or chromium. Sometimes it exhibits striking contrasting veins of magnesite.