If you have deep pockets and a fondness for lost treasure, you may soon be able to own a piece of what's considered the most valuable known shipwreck in history.

A collection of cut and rough emeralds recovered from the wreck of the Nuestra Señora de Atocha, a Spanish galleon that sank off Florida in 1622, will be offered up for sale in April by Guernsey's auction house. One emerald in particular, an extremely rare 887-carat gem called La Gloria, is considered the largest of its kind in the United States. According to Guernsey's, the final bid for this gem alone may top more than $5 million.

The La Gloria emerald, recovered from the wreck of the Nuestra Señora de Atocha, likely came from the world-famous Muzo mine in Columbia more than 400 years ago. The La Gloria emerald, recovered from the wreck of the Nuestra Señora de Atocha, likely came from the world-famous Muzo mine in Columbia more than 400 years ago. (Photo: Guernsey's)

The Atocha was part of a famous fleet of Spanish vessels that foundered on Sept. 6, 1622 after encountering a hurricane off Key West. The ship was heavily laden with treasure straight out of a pirate's dream, with reported cargo of 24 tons of silver bullion, copper ingots, 125 gold bars and discs, 350 chests of indigo, 20 bronze cannon, 1,200 pounds of worked silverware, and various gems and jewels.

Despite efforts by Spain to recover the treasure, the final resting place of the Atocha would not be discovered for another 363 years. In 1985, after 17 years of searching for the fabled vessel, famed treasure hunter Mel Fisher finally uncovered the remains of the Atocha and its cargo of gold, silver and emeralds.

The 20 cut and raw stones and 13 pieces of stunning jewelry headed to auction are all from the collection of emerald specialist Manuel Marcial de Gomar. In 1985, Marcial de Gomar was chosen by Fisher to appraise and consult on all of the emeralds taken from the wreck of the Atocha. In return for his services, Fisher paid him a portion of the gems recovered.

Some of the other gems offered up for auction were discovered over the course of Marcial de Gomar's career, including this extremely rare "star emerald," the largest of only 11 emeralds worldwide known to display the phenomena.

The 25.86 carat “Marcial de Gomar Star Emerald” is believed to the only double-sided star emerald in the world. The 25.86 carat Marcial de Gomar Star Emerald is believed to the only double-sided star emerald in the world. (Photo: Guernsey's)

Those interested in bringing home a bit of green from the Atocha can participate in the online bidding live on April 25 at 7 p.m. For those not into emeralds, a collection of gold coins from the wreck will also be offered for bidding. You can see a full listing of the incredible gems, jewelry and coins here.

Michael d'Estries ( @michaeldestries ) covers science, technology, art, and the beautiful, unusual corners of our incredible world.