Mel Fisher was the treasure hunter made famous for his 16-year search for the Spanish galleon Atocha shipwreck. His mission led to the discovery of a $450 million mother lode in the waters off Key ...

The crew of Mel Fisher’s Treasures salvage vessel, which made the discovery, estimates its value at $500,000. The rare emerald, which likely came from the Muzo mines in Colombia, is about 10 carats.

Nearly 40 artifacts from Mel Fisher's collection will be auctioned off by Guernsey's on August 5, 2015. The chalice has a starting price of $200,000, according to the auction’s website.