Erik Rintamaki was just trying to be more efficient when he took his ultraviolet light out with him on a rock hunting expedition. What he found instead has made him internet famous.

Rintamaki uses the ultraviolet light to find certain kinds of rocks that glow underneath it, but those rocks paled in comparison to the rocks he found instead.

Since dubbed 'Yooperlites', the rocks Erik found glow a bright orange with gold flecks under the ultraviolet light (more commonly referred to as 'black light', like the poster room at Spencer's Gifts back in the day).

He sent the rocks to Michigan Tech University, who found out they were a rock called syenite, an igneous rock similar to granite but without the quartz.

Kevin Cole, associate professor of geology at Grand Valley State University, told the Detroit News it's not unheard of for certain rocks to glow under certain light, but it's not common.

 He said rocks such as syenite have a crystal structure that move electrons from the sulfur they contain to glow under light.

"The ones I've seen typically fluoresce with a yellowish light," he told the News.

In the meantime, the discovery has left Rintamaki a hero in the geology world. After several interviews last week, his Yooperlite Facebook page has gone from 500 likes to close to over 4000.

There you can set up rock hunting tours with Erik, or buy some of the Yooperlite he's already found.