Sophia’s Mentz’s fortifcation agates. Photo by Hanna McGuire.

Treasures of Lake Superior: Agates

Lake Superior, the world’s largest freshwater lake, is home to so many creatures and plants; it is also home to something less thought about: agates.

The official Minnesota state gemstone, agates, were formed by lava during the North American continent split, which created a large rift valley with lava that is now Lake Superior. When the lava cooled, water went into the holes that were created by bubbles and deposited quartz, iron and various other minerals into the layers, which then created agates. When the volcanic rock eroded, agates were then released from the lava and moved to other places; which is why we can find agates around Lake Superior, according to the Minnesota Department of Natural Resources.

Agates can not only be found around Lake Superior but also throughout Minnesota. Agate collectors often look for them in gravel pits.

Micheal Braunagel, an associate professor of geology at the University of Minnesota Duluth, moved to Minnesota and is now a passionate agate hunter. Braunagel said that agate hunting is one of his favorite activities to do with his friends when they come to visit, as he is from New York.

Braunagel goes agate hunting about ten times a year but is always looking for them. He also notes that he had much success finding agates in gravel pits.

Agate collecting is a fun hobby for many Minnesotans. One public Facebook group, Collecting Lake Superior Agates, has more than 30,000 members. This group has daily updates where collectors can share their agate findings and classifications. “This is a group for those who collect Lake Superior Agates, plan to collect them, or are simply interested in learning about Lake Superior Agates,” according to the Collecting Lake Superior Agates Facebook group. This group was created in September of 2012 and has had 139 posts about agates in the past month.

Mentz with her agate collection. Photo by Hanna McGuire.

21-year-old UMD psychology and cognitive science student and agate collector Sophia Mentz shared her story about agate collecting. “I started [collecting agates] my senior year of high school because my sister’s fiancee was really into agates, and he would drag us [to collect agates] and I started to collect them too,” said Mentz.

“I like to find [agates] in gravel and rock pits,” said Mentz.

When asked what her favorite part about finding agates, Mentz said she likes finding fortification agates. “I like how pretty the small ones can be,” said Mentz. Fortification agates are just one of the many types of Lake Superior agates. They have round, wavy bands.

Mentz’s house decor, made by herself with agates she’s found. Photo by Hanna McGuire.

Mentz likes to make crafts out of her findings. She has filled a lamp with agates, and created some house decor. She also gifted her sister and sister’s husband a frame with agates as their wedding gift.

Mentz likes to dedicate days to go agate hunting. “I try to go at least once a week,” said Mentz.

“When the weather was nice, like during the summer, I was going three to four times a week,” said Mentz.

Mentz notes that she goes searching for agates at the Limnology Building, which is near Brighton Beach, if not there, she has a little beach she stops at, which is about a twenty minute drive.

While Mentz enjoys agate hunting in Duluth, many people head 40 miles south to Moose Lake.

“Moose Lake is the agate capital of the world,” said Craig Prudhomme, Financial Advisor of Agate Financial Services in Moose Lake.

Prudhomme, who is originally from New York, went to Northland College in the Midwest and has now ended up in Moose Lake. Every year, Prudhomme helps coordinate the Agate Stampede.

“I used to run outdoor programs where I was responsible for people’s lives, so safety was always an important part of what we did,” said Prudhomme.

Prudhomme explains the stampede as one and a half blocks in this little town being blocked from any traffic. The stampede starts at 1 p.m. and just before noon people start to put their lawn chairs up to reserve their spots.

“Two dump trucks loaded with 400 pounds of agates, gravel and coins,” said Prudhomme. These two dump trucks are unloaded right down the street. The dump trucks contain about $400 to $500 coins, mostly quarters, but the local movie theater gives their half dollar coins.

Before the stampede begins, Prudhomme likes to talk to people about why they live there, what’s going to happen and discuss safety measures. Then at the sound of the airhorn, agate stampeders go ahead and try to find agates and coins.

“I’m gonna guess that there were probably last year easily over 5,000 people, maybe 6,000,” said Prudhomme.

Prudhomme says that one of the most encouraging things is seeing how everything comes together; he has a small team of volunteers.

“As things are finishing up and people are checking out all the rocks they’ve thrown in their buckets, we’ll go by, especially for little kids, and just say, ‘Hey, did you find any agates?’ And if they don’t have any, I’ll let them choose from my bucket or pull one out of my pocket,” Prudhomme said.

In order to assure that people don’t go into local businesses to rinse their rocks, they have the local fire department come and fill bucks with water so people have water right on the edge of the street to rinse their rocks and hands.

Agate hunters can also go to the Moose Lake’s Soo Line Pit, where they must purchase an agate picking permit. Permits are five dollars a person and one dollar per each additional person in the group.

Agates not only make for a great hobby for Lake Superior goers, but also many businesses sell agates and jewelry made out of agates. Some shops include Agate City and Beaver Bay Agate Shop.

Each Lake Superior agate carries a story, whether found on the shore of Lake Superior or the agate stampede and brings together a vibrant community of collectors.