At 7 years old, Naomi Vaughan probably has a hard time wrapping her head around a 65 million-year span. But that's the minimum amount of time elapsed between the death of a tiny sea creature and when Naomi picked up its remains.

Bored with her sister's soccer game in Bend, Ore., last fall, Naomi started digging in the dirt and found what she thought was a shiny rock resembling the spiral-shaped amulet featured in Disney's Moana.

Spotting its pearlescence, her mother suspected the "Moana rock" was actually something more, perhaps "millions of years old." Earlier this month, her suspicions were confirmed when paleontologists revealed the rock was actually a fossil of a marine invertebrate called an ammonite, which went extinct some 65 million years ago.

"Nothing like this is known anywhere near Bend," paleontologist Greg Retallack tells the Bend Bulletin. He believes the fossil—which another paleontologist suspects is up to 100 million years old—originated at a site 100 miles away, or perhaps came from out of state, and was lost or discarded by someone.

Its missing context means the fossil isn't worth much—perhaps $20, Retallack says—compared to what CNN says is the $50,000 value of some of the rarest ammonite fossils.

But Naomi was "delighted to find something so beautiful and to discover it's so old," her dad tells the Bulletin. "She's certainly the only person in our family to make that discovery," he adds.

"She is still really excited." (A boy once tripped and found a skull.)

This article originally appeared on Newser: Bored by Soccer Game, Girl Digs in Dirt, Makes Wild Find