Gemstones have been a topic of fascination to human beings for centuries, not just for their beauty, but also for how rare ...

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 ...

Usually, what springs to mind when you think of the world’s most expensive substances are gold, silver, and platinum. However ...

From Jennifer Lopez's pink engagement ring to Kim Kardashian's 15-carat stunner, read on for a roundup of some of the most ...