Yooperlites: Lake Superior’s Glowing Rocks

What the heck are Yooperlites? And you can find rocks that glow in Lake Superior?

So, we’re sitting by the campfire and my cousin tells us about how he hunts for these rocks that glow under black light, and even has one to show us and another cousin has a black light in her car (so UP).

Essentially, they are rocks that were recently discovered (which is why I’ve not heard of them, since I was way overdue for a UP visit) by a local when he held up a few Lake Superior rocks to a black light.

Why do Yooperlites glow?

Yooperlite rocks are an intrusive rock called syenite, which is similar to granite. However, when put under a black light, the rock glows and shows a reddish/orange glow. This is due to the mineral sodalight (Na₄Al₃Si₃O₁₂Cl) which gives off the fluorescent glow.

How do you find Yooperlites?

First, research the local laws. Some beaches do not permit rock collecting. Also, the state of Michigan has a 25 pounds of rocks per year rule. Once you’re on a beach that allows rock collecting, the best time to find Yooperlites is at dusk, into the evening. Prepare to get wet, because there’s a good chance you’ll be going in the water. Many have found the glowing rocks on beaches on the north side of Lake Superior — but the general rule of thumb is if the beach has (or had) agates, it may have yooperlites.

What tools do I need to find Yooperlites?

I learned a bit about the importance of a good light from my cousin. The best light to find rocks (especially underwater) is a longwave 365nm filtered uv flashlight like this one, or this less expensive one (affiliate link). However, while Chad and my cousin were using good lights — I was using a cheapy $20 light and finding rocks just fine. However, my light would not find rocks underwater.

And you’ll need something to pick up your Yooperlites. My great grandfather used to collect agates on the very beach we were on, and I was using his spoon set up from 100 years ago. It’s essentially a slotted spoon on a dowel. And honestly, it works really well. My cousin strapped flashlights to our dowels for easy scanning.

If you plan to go into the water, you’ll want some good water shoes, a bathing suit… or if you’re my cousin, waders.

You’ll also need a bucket or bag (or in my case an apron from my family’s now closed florist – which I highly recommend if you have a dog).

What are Yooperlites worth?

Well, it depends who you talk to… The founder (and owner of the trademark) sells the glowing rocks for about $32 a pound. Some lights glow more than others, and I’ve seen palm size rocks for sale for $25 each at local shops. For us, we plan to keep the 20 and maybe create a DIY black light solar mason jar (I said maybe…).

More Tips for Finding Yooperlites

First, bring a white flashlight and some basic gear — just in case. Searching on the beach at night, especially where there is little actual beach and a lot of driftwood and fallen branches can be dangerous. Second, there’s a good chance you won’t have cell service on remote beaches, so prepare for that. Third, you will get wet, your stuff will get wet. Bring towels, a change of clothes, or whatever you need for when you get out of the water.

So, here’s a little peek into our adventure, and we can’t wait to go back out again and try to find more of these unique glowing rocks.