Yooperlites: The Glowing Rock from Michigan

Discover the Science, History, and Hunting Tips for Yooperlites

Yooperlite is one of the more interesting rocks to emerge “recently.” It’s known for a beautiful, spotted fluorescence that displays in awesome ways with UV light, but few people are quite sure of what it really is.

So let’s take a deeper dig into yooperlite rocks, and everything associated with them.

What is Yooperlite?

Technically, yooperlites are a form of sodalite-rich syenite. Yooperlite is a trade name, and we’ll touch upon that in just a moment. These stones are mainly known for fluorescing, owing to the high sodalite content in the matrix of the stones. While yooperlite sounds like a mineral name, these are actually rocks.

A rock is a conglomerate of different minerals in combination, although we often think of them as single substances. The stones themselves are predominately syenite, which is an igneous rock with a high orthoclase feldspar content. It’s quite similar in composition to granite, but it lacks the high quartz content of granitic rocks.

Sodalite, on the other hand, is a mineral. Specifically, it’s a tectosilicate mineral that occurs in massive form. Sodalite is actually a relatively recent discovery, having only been found and used within the last couple of hundred years. Sodalite is mainly known for its royal blue color and mottling with white limestone, similar to lapis, but the mineral glows under UV light.

Is Yooperlite Rare?

Not particularly. They’re not rare, so much as they come from one specific place in Michigan and don’t seem to show up anywhere else.

Because of the relative oddity of the stone, they can sometimes command a decent price. The price has been driven down since their initial discovery since most people have no trouble finding a few if they’re searching in the right area.

See below for a description of where to find your own.

Why the Name Yooperlite?

Without getting into too much controversy, the name yooperlite originally stuck as a trade name from the gentleman who “discovered” them. “Yooper” is a slang name for people from the Upper Penninsula in Michigan.

Those who are fans of these stones might have also seen them called “emberlite.”

This is due to the fact that the discoverer trademarked the name “Yooperlite” and began to take action on people selling the stones on vendors like Etsy. Hence the name emberlite came into usage to avoid legal troubles.

I usually just use the term sodalite-rich syenite, which is descriptive and removes some of the mythological feelings that people seem to derive from certain trade names.


Displaying Yooperlite

Yooperlites are interesting, but generally not all that attractive as display pieces since they can lack any real coloration. This makes them unattractive as collector’s items if you don’t have an easy way to display them.

The sodalite in the stones glows at 365nm in wavelength, so you’ll need to make sure your light covers that. In general, you’ll be looking for a long-wave UV light for these purposes. The good news is this happens to be the exact part of the spectrum where most cheap “black lights” sit.

From there it’s just a matter of making some sort of display. One of the easiest that I’ve seen is to simply buy a cheap aquarium kit and replace the light with a black light. While most modern aquaria come with LED lights, you can still find old fixtures in thrift stores and online for just a few bucks. Then it’s just a matter of matching the length of the fixture to a black light tube.

Quite a few stones are reactive to long-wave UV light, so you can also display others in the same area.

Other people go to much more extensive lengths to build actual UV cabinets and displays, either by altering existing furniture or from scratch.

Where Can I Find Yooperlite?

Yooperlite is found only along Lake Superior’s shore of Michigan’s Upper Peninsula. Specifically, this is the northern portion of the Upper Peninsula and they’re generally found along the shores of the lake itself.

Most seem to originate from the stretch of beach centered north of Newbury. This is a great spot to begin your own hunt for Yooperlites.

Some have also shown up a bit further from this location, but always on the shores of Lake Superior. So, you may want to bring along a good UV light even if you’re far from the normal location where they’re found.

Tips for Finding Yooperlite

The problem for most people who can get out there is actually finding them. The vast majority of yooperlites look fairly ordinary without the UV light, although some with particularly high sodalite content may resemble pretty blue rocks at first glance.

What you’ll want to have on you is a strong long-wave UV light. The uvBeast comes with strong recommendations from many rockhounds. The stronger the better, since the rocks should continue to fluoresce for a short period after you shine the light on them.

Great For Minerals!
We earn a commission if you click this link and make a purchase at no additional cost to you.

It’s much easier to see the glow of these stones at night than during the day, just remember to bring a normal light and to be careful about your footing during the excitement of the hunt. Yooperlites will show up as orange when the light hits them, and continue to glow for just a bit after from the absorbed UV light.

Move methodically across an area, sweeping it with your black light slowly. If you can keep your patience, then then the slower the better in this case. It shouldn’t be too hard to find them, provided that you’re in the right area.

They’re really not that rare, the main thing delaying their discovery was likely how unremarkable they are without a UV light shining on them.

So get out there and find your own!

Share This Article With a Friend!

The Rock Seeker Rockhounding Club
  • Online rock and mineral club for collectors of all levels!
  • Find community with like-minded rock and mineral enthusiasts.
  • Monthly Giveaways!
  • Free Access to Entire Digital Library of Products (annual memberships)
Join Now!
Unbelievable Mexican Agates (cut and polished!)