Shellers, set your course for Folly Beach!

Folly Beach Pier
Credit: sestevens/Getty Images

When Ashby Gale, the owner of Charleston Fossil Adventures, found a teardrop-shaped oyster shell encrusted in concrete-like limestone on South Carolina's Folly Beach in 2015, he knew it was special.

In the years since, Gale has collected hundreds of similar shells. And now, four years after that first fateful find, science has confirmed what Gale had long suspected: they're hardly a novelty.

With help from College of Charleston paleontologist Robert Boessenecker, The Post and Courier reports that the shells have finally been identified as ancient Ostrea coxi oysters. Remnants from ancient shellfish that lived 3 million to 5 million years ago, Ostrea had never before been found in South Carolina. Until now, they'd only ever been identified in Florida.

According to The Post and Courier, the shells are believed to have ended up on Folly because of the city's 2014 beach renourishment project, when the rocky sand from a shoal three miles offshore was brought in to combat erosion.

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"Pretty much all of those gray rocks that Folly residents complain about since the botched 2014 beach renourishment are pieces of Goose Creek Limestone and almost always have shells or shell fragments inside," Boessenecker told the paper. "On occasion you can find nice scallops, oysters and rare sea snails."

Or, it would seem, a plethora of ancient oyster shells.

Ostrea coxi oysters
Credit: Robert Boessenecker

Today, The Mace Brown Museum of Natural History at the College of Charleston has upwards of 30 of them in its collection.

"If you know what to look for you can pretty much pick up one of these Ostrea coxi teardrop oysters almost every visit or every other visit to Folly," Boessenecker said.