Gemstones, including rubies ... Low-quality alexandrite can sell for as little as $100, but high-quality stones can sell for tens of thousands or even hundreds of thousands of dollars.

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 ...

New York-based, upmarket gemstone dealer has created a series of oil paintings entitled "Tree Portraits" that celebrates the ...

The July sale, far from vindicating the government's stance, underlines the growing international clamour for high-quality coloured gems, but Gemstones remains in discussion with the Zambian ...