When you think of expensive gemstones, what comes to mind? Most people think of the Big Four: diamonds, emeralds, rubies and sapphires. However, it might surprise you to know that there are ...

Narrator: High-quality black opal can cost over $10,000 per carat, making it one of the world's most expensive gemstones. But mining black opal isn't easy. After investing tens of thousands of ...

From intricately designed pawns to boards from luxury brands, check out the most expensive chess sets in the world.

High-quality black opal can cost over $10,000 per carat, making it one of the world's most expensive gemstones. Over 90% of black opals come from Australia, but they aren't easy to find.

Throughout history, the richest people have owned or gifted their loved ones with extravagant rings, including the rarest gemstones. Here’s a look at some of the most expensive rings in the ...