From KOAT.com via Geology.com:

Jetter is talking
about a 306 carat, black opal from Australia, buried in the earth for
the last 400 million years. An Australian miner named Bobby discovered
the stone and is now ready to share it with the world. He selected
Jetter to create a one-of-a-kind piece of jewelry to sell, and then
share the profits.

Thirteen
years ago, Bobby retired from a long and hard career in the mining
industry. He sold his tools and was about to call it quits, when someone
handed him one last bucket of dirt. To his incredible surprise, Bobby
saw something shinny. Turns out, it was one of the world’s most rare,
valuable and precious stones.