This is a Crystal Opal Stone which comes from the opal mines of Coober Pedy, South Australia. This would make a very nice ring stone or small pendant. This has been very difficult to photograph as the colours don not really show up until you move the stone. This stone is best seen in natural light. It shows Purple. Green, Yellow, Blue and Orange.
If you see an opal on this website that you might like to have as a pendant, please contact Peter to discuss if it is possible with that particular stone.
You also need to state if you wish to have a bail fitted or not. If you do, then you would need to be charged for the cost of metal, silver or gold.