In 1985 treasure hunter Mel Fisher and his team found the wreck of Nuestra Señora de Atocha — a Spanish galleon that sank in a hurricane in 1622 near what is now Key West, Florida. Fisher initiallyfound more than half of the ship’s registered cargo in one cache — an estimated $450 million in gold, silver, precious stones and artifacts.

Fisher hired Manuel Marcial de Gomar, an emerald specialist, to appraise the salvaged raw and cut stones. An assortment of them that Marcial received as payment is included in an auction that will take place at New York-based Guernsey’s. The auction will begin on April 25.

CNN reports that the auction includes the 4.39-carat Queen of the Sea, estimated to sell for $250,000 to $350,000, and the Nine Pillars of the Andes — nine emeralds totaling more than 91 carats that carry an estimated value of $2.5 million to $3.5 million.

This video from Fox News has more:

Fisher, who died in 1998, and his team have recovered more than half a billion dollars of treasure from the wreck — 40 tons of silver and gold, including more than 100,000 Spanish silver coins, gold coins, Columbian emeralds, silver and gold artifacts and more than 1,000 silver bars — and there is an estimated $250 million in treasure yet to be found.