Keith and Linda Stetzer found the 3.02-carat ring and took it to Mervis Diamond Importers in Tysons Corner, Va., where it had been purchased, The Washington Post (NYSE:WPO) reported Sunday. A Mervis stamp on the ring led the couple to the jewelry store.

"People are just very careless. That's why we have lost-and-founds," said Ronnie Mervis, owner of the store.

Mervis said he can have workers inspect the diamond in an attempt to identify it, but it is not easy to link a piece of jewelry to a buyer.

"It would be easier if it goes the other way, if someone comes to claim it and says, 'My name is Jones.' Then we can search for it. Otherwise, it's a needle in a haystack," he said.