Polished Green Opal rock GREEN83 chalcedony Dimensions at widest points approximately

Dimensions at widest points approximately 110 mm x 60 mm x 30 mm thick

Weighs 80 grams

with great weathered rough side

Weighs 914 grams

Dimensions at widest points approximately 140 mm x 80 mm x 60 mm thick

Polished Green Opal rock GREEN83 chalcedony Dimensions at widest points approximatelyGREEN83 Green Opal & Magnesite rough rock, cut and polished on one side with a rough, naturally weathered back Dimensions at widest points approximately 180 mm x 100 mm x 75 mm thick Weighs 1,834 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.