A giant opal that weighs nearly 12,000 carats received a six-figure bid at an auction in Anchorage, Alaska. The precious stone, which is split in two, was sold for $143,750 on Sunday by Alaska Premier ...

Little was known about the preconditions for the formation of opal - knowledge that would have given hints on where to look for it. Powerful data mining software developed by University of Sydney ...

There’s a good chance you might not, because though their intricate appearance sets them apart from other gems, opals have fallen out of favour in fashion over the years. While they experienced ...