17/03/2017 11:52 GMT

Teenager Kalel Langford Finds 7.4 Carat 'Superman Diamond' in Arkansas State Park

The gem is the seventh largest ever found on the site.

A teenager has found a 7.4 carat diamond in a state park in America worth around half a million dollars.

Kalel Langford had only been searching at the Arkansas Centre of Diamonds State Park for 30 minutes when he found the dark brown gem - the seventh largest diamond found in the park since it opened in 1972. 

While the value of the rock - named Superman’s Diamond by the 14-year-old comic book fan - has yet to be determined, an 8.5 carat diamond found at the park in 2015 was valued at $500,000 (£404,000).  

Arkansas Crater of Diamonds State Park
Teen Kalel Langford found a 7.4 carat diamond in a US state park - in just 30 minutes 

Langford and his dad Craig were walking in the south of the park when the teen found the diamond, which is “about the size of a pinto bean” and “very dark brown, similar to coffee”. 

“It was just a few inches from a stream of water, with a bunch of other rocks that were about the same size,” the schoolboy said in a statement on the park’s website. 

“Its colour was so dark that we weren’t sure if it was a diamond, but we knew we needed to have it looked at,” his father added.   

Arkansas Crater of Diamonds State Park
The gem has been described as a 'truly extraordinary find' 

Park interpreter Waymon Cox said it was a “truly extraordinary find”. 

“Conditions were ideal for Kalel to find his diamond. About an inch of rain fell on the plowed search area during the week,” Cox said.

“A heavy rain can uncover larger diamonds near the surface. Diamonds have a metallic-looking shine and are often easier to spot on top of the ground. 

“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,” he added.

“We are all very happy for him.”  

Arkansas Crater of Diamonds State Park
Langford plans to keep the 'Superman Diamond' 

Despite the potential worth of the diamond, Langford said he plans to keep the rock as a souvenir of his visit to the state park, where tourists can pay $10 to search for gems. 

In 1924, the largest diamond ever discovered in the US was found in the area. Named the Uncle Sam, the white diamond weighed 40.2 carats. 

Since the park opened more 45 years ago, more than 75,000 diamonds have been unearthed.