This is a shaped and polished, ready to mount or display, natural Andamooka opal from the mines of Australia.
It is a freeform cushion shape, polished on one side and is 17mm high, 11mm wide, 4mm thick and of 6.85 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. This natural opal has a pale brown background, with muted pin-fire flashes of green, red, blue and yellow.
Not a great stone and should be considered an example of this type of opal.