Not too far beneath our feet in Charleston sits a literal goldmine for fossil hunters, a shallow layer of rock filled with fossilized bone and teeth. Thankfully you won’t need to go digging to find the treasures inside it.

“Anytime dredging occurs we have the rock layers pulled up from the bottom, up to 30 million years back, and we can find all the fossils that come from them,” says Paleontologist Ashby Gale, owner of Charleston Fossil Adventures.

“So that’s why some areas around the harbor have pretty phenomenal fossil collecting,” adds College of Charleston Paleontology professor Bobby Boessenecker. “Ice age mammals, sharks, bony fish, sea turtles, occasionally sea birds, and lots of marine mammals are readily found here.”

Each fossil expanding our knowledge of what the Lowcountry looked like millions of years ago. These black triangles also tell a more “recent” tale- one that follows Charleston as it emerged from the Civil War. Two stories, separated by millennia, linked to that rock layer filled with fossils…and phosphate.

Small nodules of phosphate seen throughout the Lowcountry.

These black rocks dot every stream, river, and beach in the Lowcountry- and were generally ignored until the late 1860s when two Charleston scientists discovered that these rocks are composed of concentrated phosphorus- perfect for fertilizer, then necessary for the large plantations that no longer had an enslaved workforce. Large mining outfits, including the Ashley Phosphate Mining Company (the origin of the often traveled road up on I-26), sprang from this discovery and started stripping the land and rivers for the valuable rocks- using freed slaves, working in deplorable conditions, as cheap labor to harvest the phosphate nodules.

An illustration of the Stono Phosphate Works.
Courtesy of The Charleston Museum

“But the miners would often find lots and lots of shark teeth, mammoth bones, teeth, marine mammal bones, etc,” says Boessenecker.

Interestingly these discoveries worked their way into advertising for the “miracle mineral,” which helped Charleston prosper as other areas struggled economically in the postwar South. At one point, Charleston produced one half of the world’s phosphate!

An advertisement for Carolina Phosphate featuring two marine reptiles and fossils from the late 1800s.
Courtesy of The Charleston Museum

This boom was not to last, as phosphate mining declined by the turn of the century in Charleston. Years later, this brief blip in post-war Charleston still provides plenty of opportunities for fossil hunters as Gale explains, “Much of West Ashley and the historic plantation district as we know it today is tilled over soil that has had all the phosphate stripped out from underneath it.”

Making it quite easy to find treasured trophies, and incredible discoveries in Charleston compared to other fossil rich areas across the nation & the world- a result of our Lowcountry geology, a long lost industry, and the current dredging to expand industry.

Consider visiting the Mace Brown Museum of Natural History at the College of Charleston and the Charleston Museum for their exhibits and collections detailing the area’s vast and diverse fossil history. For the more adventurous, Gale leads sustainable, ethical, and legal amateur fossil collecting expeditions. For more information on these tours, head over to the Charleston Fossil Adventure’s website.

Images used in this story courtesy of The Charleston Museum, Charleston, South Carolina.

Storm Team 2 Meteorologist David Dickson