This is a Solid Black Opal from Lightning Ridge in New South Wales, Australia showing a lovely Blue, Green and Purple colours. N7 with a Brightness rating of 3.5. This stone would be Ideal for setting in a ring or a small pendant.
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.