White, pink, yellow and blue opals hide in the rocky landscape of Spencer Opal Mines, the largest-producing precious opal mine in the United States.

A toe bone of Fostoria, preserved in opal. (Photo by Robert A. Smith, courtesy Australian Opal Centre) In another project, paleontologists recently discovered a new spike-armored dinosaur in Texas.

Gemstones are precious, especially when they come filled with dinosaur bones.Back in the 1980s, a miner unearthed a slew of fossils preserved in opals in an opal mine near Lightning Ridge in ...

The new dinosaur fossil was found in an opal mine and has turned into the gem itself, making it the most complete opalized dinosaur skeleton in the world, according to a new study.

While the largest uncut opal is the Olympic Australis at 17,000 carats, Caldwell’s 6,265 carat opal is firmly in the world-class league. Caldwell’s 6,265 carat opal.

The Rainbow Ridge Opal Mine, which also features a gift shop, is located about 35 miles west of the Denio Junction via State Route 140. The road, which is marked, is paved until the last 7.5 miles, ...

This Virgin Valley opal mine is open Memorial Day through Labor Day Weekend. Tools are available to rent, and it’s $70 a day to dig. 30 miles west of Denio on U.S. Highway 140, 775-375-5955.

It was named in honor of Robert Foster, the opal miner who discovered the fossils in the 1980s, and the sheepyard where the bones were found. The bones were preserved entirely in opal and are a ...