Collectors desiring to own true pirate treasure have fewer than a handful of coins to consider.

One of at least three coins available in private hands comes from the wreck of the Whydah Gally, which was discovered by Barry Clifford and his team off the coast of Cape Cod in 1984. One of the coins is being offered in an April 29 and 30 auction conducted by Daniel Frank Sedwick LLC.

The Whydah is the only true pirate ship to have been located, and it carried a bundle of sunken treasure. But Clifford hasn’t sold any of the coins to the collector market. He instead put them on display at a museum in Massachusetts and sent them around the country in paid exhibits through National Geographic, which has also produced a video documentary about the wreck and its recovery. Recovery efforts were ongoing as recent as late 2013, and coins continued to be discovered then.

However, according to Agustin "Augi" Garcia with the auction firm, early on in the recovery efforts, a small number of coins were distributed to investors and family. Many of those coins were bought back by the salvors, but some were never located and returned. The Sedwick firm has previously sold two other known examples, Garcia said, but "there may be a few more" out there, he said.

The Whydah was a slave ship that was captured by notorious pirate captain “Black Sam” Bellamy in February 1717, just two months before it sank on April 26, 1717. The wreck killed Bellamy and all but two of his 145 men, and took some 4.1 tons of gold, silver, and other pirate treasure down with it. 

The example now being offered in the Sedwick auction was consigned by shipwreck expert and author Tom Sebring. 

The silver 8-real coin was struck at the Mexico City Mint during the reign of Philip V, and the partial date suggests it may have been made in 1712, a few short years before it was likely captured from 1715 Spanish Plate Fleet ships by the pirate Bellamy.

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Sebring told Sedwick that “he got more enjoyment out of owning this coin than any other shipwreck piece in his collection,” according to the auction firm.

How the coin came to the market is unclear, but the demand for real pirate treasure can’t be denied.

Sebring bought the coin in Sedwick’s sale No. 10 in Oct. 25 and 26, 2011, where it hammered for $7,000, more than 10 times its high estimate.

In the current Sedwick sale, the coin has an estimate of $3,000 to $6,000 and up. The current bid as of April 23 is $3,750.

For more information about the auction, or to bid, visit the firm’s website.