Colombia produces the world's most expensive emeralds — a treasure that's been fought over for centuries.

Colombia's emerald industry used to be far more dangerous, with frequent explosions inside the mines — and gun battles on the outside.

Emeralds encrusted in white calcite rock inside the mine at Muzo in central Colombia. They will later be analyzed at a laboratory to determine their worth. Colombia's emerald industry used to be far ...

Colombia's emerald industry used to be far more dangerous, with frequent explosions inside the mines — and gun battles on the outside.

Colombia's emerald industry used to be far more dangerous, with frequent explosions inside the mines — and gun battles on the outside.

Inside the emerald mines that make Colombia a global giant of the green gem NPR ventures into a Colombian emerald mine — which used to be more dangerous, with potential explosions inside and ...

MUZO, Colombia — Although he has helped transform Colombia's emerald industry, long a source of violence and environmental damage, former U.S. diplomat Charles Burgess admits that he got into ...