The emerald was discovered in a beryl mine in 2001 and later smuggled out of the rainforest and to the US by mules — one of whom was reportedly attacked by a panther during the mission.

Estimates of its worth vary but are as high as $925 million. The emerald, Brazilian authorities say, was discovered in a beryl mine in the country in 2001 and later smuggled to the U.S. There ...