Judging from the picture, this is not a natural opal, but a relatively common artificial opal.

The truth hurts.

Opals are often called "noble gems". It belongs to one of the five precious and high-grade gems in the world together with the variable stone. The most famous opal producing areas in the world are Trana Bula and Goyle in the southwest of Sri Lanka. Opals are also found in Brazil and Russia, but they are very rare.

Provide a reference message and you will be clear.

In the preview of Christie's Jewelry and Emerald Jewelry Auction in Hong Kong, the model showed a giant cat's eye Alexandrite of 2 12.76 carats. According to the agency, this is the largest cat's eye emerald in auction history, with an estimated value of HK$ 7.85 million.

If your opal exceeds 40g, it is priceless.

I hope the answer can help you.