What is a Yooperlite? The Mysterious Glowing Rocks
“A gem and mineral dealer in the U.P. has made a glowing discovery. Erik Rintamaki discovered a rock that glows under an ultraviolet light made of a mineral never seen before in Michigan. Without knowing what they were or why the rocks glowed, he named them “Yooperlites,” so the story goes.”
Our Upper Michigan residents & enthusiasts already have plenty of reasons to enjoy wandering through the rich, natural world that’s found in this treasured northern peninsula. There’s something new to discover within every one of our acres, and so that innate sense of adventure and discovery has developed into a familiar passion for outdoor hobbies. In fact, that sense of adventure and discovery has become a significant part of our culture, so when anything new & interesting is gaining traction here in our slice of Michigan, we feel as though it’s deserving of a little extra… digging (this joke will make sense in a minute).
Northern Michigan is ripe with plenty of things to do during the day, and even as you relax into your evening, there’s usually some stargazing to be done, a camp to settle into or a bonfire to visit. If, for whatever reason, that’s just not as exciting as you like your evenings to be, there’s been some growing popularity recently for a different kind of nighttime U.P. adventure; rock hunting! “But, at night?” – you’re surely wondering, but don’t worry, we’ll clear up any confusion here for you. There’s actually a fair amount of enthusiasm for rock hunting all across Northern Michigan, and there’s a good reason for it! There’s all kinds of spectacular, collectable rocks washing ashore up here; Lake Superior agate and Michigan greenstones among them. However, the rocks we’re talking about today are different from the rest, because they can only be found… you guess it… at night! They’re Yooperlites!
What is a Yooperlite?
Before we go any further, it’s worth noting that a ‘Yooperlite’ is actually a trademarked brand of what is officially known as a “syenite rock rich with fluorescent sodalite”. But if you’re unsure of what exactly it is we’re talking about here, a ‘Yooperlite’, in short, is a special kind of fluorescent rock that you can find predominantly along the shores of Lake Superior that, as the trademarked name suggests, can glow when subjected to specific lighting conditions. This fascinating discovery is owed to Michigan man Erik Rintamaki, who also holds the aforementioned trademark, that resulted from a seemingly innocent shoreline stroll late one evening. He credits the discovery to curiosity sparked from simple conversations around what the Lake Superior shoreline might look like when subjected to ultraviolet light. The idea came about after Erik was told how UV lighting can interact with certain minerals. Years later, Erik stumbled across an affordable hand-held UV light online and immediately purchased one “one a whim” .
Strolling onto the shoreline at 4 am one fateful morning back in June of 2017, using his new UV light, Erik would make his initial discovery after finding two small Yooperlites, each “about the size of a dime”. When shone on with a UV light, to his surprise, these small stones emitted what is now a distinguishable teal-yellowish luminescent glow. The discovery would garnish a staggering amount of national media attention and has since inspired Erik to pursue a mentorship role within his community. Offering yearly Yooperlite tours & expeditions, Erik will accompany and educate rockhounds & rock collecting enthusiasts on a long walk along the Lake Superior shoreline in search of these incredibly unique rocks. , however, there is a considerable effort to encourage discovering these sodalite-rich syenite rocks for yourself. The best spots to search for Yooperlites appear to be along the Keweenaw Peninsula and further east over by Whitefish Point, but with a chance to unearth Yooperlites on any night of the year, there’ll be plenty of opportunities to plan out this unique adventure.