A California woman visiting a public mine at an Arkansas state park last month went home with a 4.38-carat yellow diamond that she found resting in the soil.

Noreen Wredberg of Granite Bay, California, discovered the rough stone at Crater of Diamonds State Park, where she and her husband, Michael, made a pit stop while visiting Hot Springs National Park, according to NBC News.

“I first saw the park featured on a TV show several years ago,” she told the parks department. “When I realized we weren’t too far away, I knew we had to come!”

The Wredbergs were at the park Sept. 23, only a few days after an inch of rain fell in the area, making the ground ripe for harvesting gems.

Their timing, it seemed, was impeccable.

Wredberg said she searched the ground for about an hour before spotting an unusual glimmer out the corner of her eye.

“I didn’t know it was a diamond then, but it was clean and shiny, so I picked it up!” she said, according to NBC.

There was no immediate indication of how much the yellow diamond could be worth, but as the finder, Wredberg gets to keep the gem as park rules allow.

She said she isn’t sure yet what she’ll do with it.

The park confirmed Wredberg’s diamond was the largest found since an Arkansas man found a 9.07-carat diamond in September last year.