If you’ve scoffed in the past at stories of visitors to Arkansas’ Crater of Diamonds State Park who have walked away with valuable gems, maybe this will blow your jaded mind: A 14-year-old found a 7-carat diamond there last weekend just half an hour after he arrived. And as big as this diamond is, the park says the stone isn’t even in the top five of the largest diamonds found there.

While some parks forbid visitors from walking out with precious finds, Crater of Diamonds has a “finders, keepers” policy when it comes to diamonds and other minerals turned up at the park — though you can’t just take home buckets of unsifted dirt.

The teen — who was visiting with his family — was walking along near the East Drain in the southern part of the park, when he espied the shiny, dark brown diamond, the park says.

“It was just a few inches from a stream of water, with a bunch of other rocks that were about the same size,” he said.

His dad says the family had only been looking around for about 30 minutes, and due to the gem’s dark color, they weren’t sure if it was a diamond at all. Just to be sure, the family stopped by the Diamond Discovery Center to have their finds identified before leaving the park. The teen says he was shocked to learn that he had found one of the biggest diamonds in the park’s history — the seventh largest, specifically.

The park’s interpreter says conditions were ideal for the find.

“About an inch of rain fell on the plowed search area during the week,” explains Waymon Cox. “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.”

The teen named his gem, “Superman’s Diamond,” well, because he happens to share a name with the comic book superhero. He says he’s planning to keep the diamond as a souvenir.

While it’s unclear how much the teen’s diamond could sell for if he decided to go that route, a fellow teenager sold a 3.85-carat yellow diamond she found at the park for $20,000 in 2014.

The largest diamond registered at the park was an 8.52-carat white diamond named the Esperanza that was discovered by a Colorado tourist in June 2015.

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