Solid Lightning ridge black opal oval cabochon cut. Due to the opals 15mm length it would lean to a nice ring or pendant.
Measurements: 15mm x 6.10mm x 3.40mm thick.
Colour: rolling blue flash. In certain lights such as sunlight, surface lights up with an electric blue rolling flash. A bluish green coloured flash can also be notice when the stone is tilted or rotate at certain angles.