Andrew London was collecting shells on Folly Beach a few weeks ago when he bent over to pick up what looked like a piece of driftwood.

"I thought it was a stick," he said. "I was going to throw it back, and then I noticed it was heavy."

The College of Charleston junior realized it might be a human bone.

London took it to the college's archaeology department, and experts there told him it was probably the right femur of a man who died a long time ago.

On Wednesday he took the bone to the office of Charleston County Coroner Rae Wooten. "I think it's definitely human," she told him, but she said she could say little more sure until a forensic anthropologist inspects it.

"It's been somewhere a long time," she added.

State Archaeologist Jonathan Leader said remains of Union soldiers with the 55th Massachusetts have been unearthed in the middle of Folly Beach before, and London's find could have come from that burial site.

Asked if he were surprised to learn that a bone had washed up, Leader replied, "Very little surprises me at this point in time. I'm just glad somebody responsible came across it."

State law says anyone who finds human bones is supposed to contact their county coroner, and many do.

Wooten thanked London and said his visit wasn't unusual. Less than a week ago, someone turned in a human jawbone.

"I have an intact femur that I've had for several years that washed up on somebody's dock on a creek. It was in real good shape actually," she said. "Sometimes we get full skulls. Sometimes we get full skeletons."

Wooten said anyone who discovers remains should not disturb them and call law enforcement. "Our primary concern is whether it's related to a death that has been investigated or needs to be," she said.

Some skulls are kept in storage for a long period because their distinctiveness could help solve cold cases, Wooten said. Other bones often are stored for shorter periods before they're cremated and disposed of in a suitable, respectful way.

Also, the coroner's office often is asked about bones that are from animals, not humans.

"We just ask that they not bury them somewhere to get found again," Wooten said.

Reach Robert Behre at rbehre@postandcourier.com or 937-5771.