Don Fassbender of Marquette is an avid scuba diver who maintains a YouTube channel about his hobby. Recently he found “Yooperlites” — rocks that glow under ultraviolet light — in Lake Superior near Marquette. (Photo courtesy of Don Fassbender)

MARQUETTE — It’s what you’d call a niche hobby.

Don Fassbender of Marquette scuba dives, but he does so using ultraviolet light.

That’s allowed him to find unusual glowing rocks called Yooperlites, which have made national headlines lately.

Fassbender has special scuba UV lights, which he was using recently in Lake Superior near the Marquette Lighthouse where he found a few Yooperlites.

That led him to believe there might be more, so he set out again in search of the unusual rocks.

“On the next night dive opportunity, I took the lights with me and I used the UV setting, and I found them in the lake, right there along the pipeline,” Fassbender said.

That pipeline is found between the lighthouse and the Coast Guard building, he said.

Although most rock hounds probably don’t have Yooperlites in their collections, Fassbender read they’d been discovered near Houghton and northern Wisconsin.

“I think they’re all around the Lake Superior watershed, so I decided to look in Marquette, and sure enough, there are some right here,” Fassbender said.

According to yooperlites.com, Yooperlites are syenite rocks rich in fluorescent sodalite. Recently found by the Upper Peninsula’s Erik Rintamaki, they resemble gray rocks to the naked eye, but under UV light, the mineral composite makes the rocks glow.

Rintamaki and his discoveries have been featured in Forbes magazine, CBS News and many other media outlets.

A Sept. 11 article in the Detroit Free Press said Rintamaki, who lives in Brimley, was on a Lake Superior beach during the summer of 2017 to look for another notable geological find, agates, and failed in his first three quests. On the fourth trip, he came across three dime-sized fluorescent stones.

In December, Michigan Technological University geologists told Rintamaki he might have come across something never seen before in Michigan, and after testing and analysis, the rocks were sent to the University of Saskatchewan, which confirmed the Michigan Tech geologists’ findings.

It was Rintamaki who came up with the name “Yooperlite.” He even maintains a Yooperlites Facebook page.

That page has an environmental bent, with one post reading: “Since Yooperlites and hunting them with UV lights is getting so popular, I would like to start something I call #CLEANTHEBEACH. If everyone that goes out just picks up one piece of trash off of the beach, each time it will make a huge difference.”

Noting that manmade trash fluoresces a lot and and is easy to spot, the post ended thusly: “Let’s clean up Lake Superior so everyone can enjoy her beauty for generations to come.”

Fassbender loves scuba diving, as do many other people, but it’s a unique experience when UV lights are used because they react differently with animals, he said.

“I did shine the lights on some crayfish, and I saw that they reacted and they look green underwater, so it interested me some in that spectrum — that light spectrum — which is invisible to the eye,” Fassbender said.

Using ultraviolet light, though, does have its challenges.

“The problem is it’s so dark that you can’t use regular dive lights at the same time, so you’re diving in black light looking for a few lights that will interact with your lights,” Fassbender said. “You’re diving blind, essentially.”

He’s found at least one other notable object in his scuba diving journeys: an expensive bicycle stolen from the Iron Bay Restaurant & Drinkery in Marquette.

An Aug. 29 Iron Bay Facebook post detailed the incident.

“What a story! Late last Friday night, Iron Bay Bar Manager Brandon Maki’s bike was stolen from the bike rack outside the restaurant. Offering a cash reward for anyone who found it, all Brandon could do was wait and see if it turned up. On Monday, he got a message. A message from local scuba diver Don Fassbender — he just happened to be exploring the waters when he found the bike near Lower Harbor, at the bottom of Lake Superior!

“Though the chain had already started to rust, Lakeshore Bike said they’d be able to fix it right up. Don refused Brandon’s cash reward, saying he was just glad he could help. Brandon did, however, give him two growlers of Bell’s Oberon from the Iron Bay Tap Room for his sincerest gratitude.

“We’ve got a great community here in Marquette, and even when bad things happen there are always people there to help — in this case finding a bike in the depths of Lake Superior! Thanks so much to Don, Jay Parent, and everyone else who helped out. Brandon can’t thank you enough!”

Fassbender said he was diving near the Lower Harbor when he made the discovery.

“It was a bigger bike,” he said. “The ones I’ve found before are usually little kids’ bikes.”

He went back to his house to get a rope, and then returned to pull up the bike. That night the Facebook post that mentioned the reward came up, which allowed him to take the next step in his recovery mission.

Fassbender connected with Maki the following day at Lakeshore Bike.

“I didn’t expect him to bring the growlers,” Fassbender said.

No matter what other treasures he finds while scuba diving, he always will have his experiences of combining ultraviolet light, geology and Lake Superior to find Yooperlites.

“It’s a very freaky experience,” Fassbender said.

To watch Fassbender find objects of all sorts underwater, visit his YouTube channel.

Christie Bleck can be reached at 906-228-2500, ext. 250. Her email address is cbleck@miningjournal.net.