Since 1906, an estimated 75,000 diamonds have been discovered at the park in Arkansas; the latest is a 3.81-carat brown diamond.
David DeCook of Stewartville was walking in the park with his family when he noticed what he believed to be a candy bar wrapper and stopped to pick it up.
Assistant Park Superintendent Waymon Cox told the Daily Mail that recent rainfall has made it easier for visitors to spot diamonds.
“April has been a very wet month at the park, with more than 12 inches of rain,” Cox said.
“Many of the park’s largest diamonds are found on top of the ground. As rain falls in the search area, it washes away the dirt and uncovers heavy rocks, minerals, and diamonds near the surface.”
Commemorating the discovery, DeCook named the copper stone The Duke Diamond after his dog. So far this year, more than 200 registered diamond discoveries have been made at the park, with this stone being one of five weighing more than a carat.
Other notable discoveries include a two-carat diamond in July, found by a father and son from Arizona, and a 7.46-carat brown diamond spotted by a French tourist in January.
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