This is 2 x shaped and polished, ready to mount or display, natural Andamooka matrix opals from the mines of Australia.
Both pieces are polished on one side, the largest is 15mm by 12mm and 2.50mm thick. The smallest is 11m by 10mm and 2.50mm thick, which combined comes to 5.75 carats.
These opals are not of the quality from other areas in Australia and are often boiled in sugar to darken the background to enhance the colour plays. Both natural opals have a white streaked brown backing stone with intermittent flashes of green, red and blue.
Totally unique stones, which could be made into jewellery or simply kept as a sample of this type of opal.