Is a type of common opal that show an interesting fluorescence either at long,medium at short waves UV light. It's fluorescence is cause by purple fluorite,while the white area is hyalite contaning traces of uranium.Full description in the Gems and Gemology of Spring 2012.
Is also called Royale Blue or Purple Mexican Opal.
So far hase been cut in cabochons but not as facetted stone.
The location is central Mexico.