Polished Green Opal slab GRN112 green stones 75 billion years

75 billion years

Weighs 586 grams

Dimensions at widest points approximately 65 mm x 50 mm x 50 mm thick

80 mm x 60 mm x 30 mm

Dimensions at widest points approximately 190 mm x 85 mm x 10

Polished Green Opal slab GRN112 green stones 75 billion yearsGRN112 Green Opal & Magnesite slab, cut and polished on one side . Dimensions at widest points approximately 110 mm x 90 mm x 10 mm thick Weighs 171 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..