A teenager stumbled across a large 7.44-carat diamond on the edge of a stream while walking through a state park in Arkansas.

Kalel Langford, 14, spotted the rock at Crater of Diamonds State Park in Murfreesboro. It is the seventh largest diamond discovered since the park was established in 1972.

The teenager has nicknamed the stone Superman's Diamond because of his love of the Man of Steel and plans to keep it.

He said: "It was just a few inches from a stream of water, with a bunch of other rocks that were about the same size."

Image: The brown diamond is the size of a pinto bean. Pic: Crater of Diamonds State Park

The park has not provided an estimated value for the diamond.


But a 3.85-carat diamond which was found in the park by another teenager in 2014 was reportedly later sold for $20,000.

Another found at the park a year later, a 8.52-carat white diamond, was valued at $500,000, the park said.

Waymon Cox, park interpreter, described the stone as the size of a pinto bean and the colour of coffee.

He said: "This diamond is a truly extraordinary find.

"It was Kalel's dream to visit the Crater of Diamonds State Park, and now he will always be part of this park's remarkable history. We are all very happy for him."

The largest diamond ever found in the US - the 40.23 carat Uncle Sam - was also found in the park in 1924.

Visitors can pay $10 to search for diamonds at the park.