Lake Superior Agates
If you're interested in treasure hunting, consider hunting for some Lake Superior agates.
In 1969 the Lake Superior agate was designated by the Minnesota Legislature as the official state gemstone. Agates found in Minnesota have a different color scheme than agates found in other parts of the world.
Their rich red, orange, and yellow coloring is caused by the oxidation of iron. The concentration of iron and the amount of oxidation determines the color within, or between, an agate's bands.
Agates are found in a variety of sizes from about the size of a pea to about the size of a bowling ball. The very large agates are extremely rare.
Small agates are often polished to make jewelry. Larger agates, called “lakers,” are sometimes cut into thin slabs that display the colored bands inside.
We recommend Agates of Lake Superior: Stunning Varieties and How They Are Formed
Our favorite Duluth Minnesota vacations always include some time to relax on the beach and hunt for agates pretty much anywhere on the shoreline between Duluth and Two Harbors.
Where Do We Hunt for Agates?
Every year our family spends a few days in a cabin on the North Shore of Lake Superior. The cabin is right on the rocky shore of the great lake.
We have many activities that we want to do while we are there in one of our favorite vacation spots on earth and agate hunting is high on the list.
When our kids were growing up they loved to just hunker down on the shore and sort through rocks looking for agates. Over time they became "experts" at recognizing the characteristics of agates. We bought a rock tumbler and spent many hours polishing up our finds after we got home.
I still have a huge plactic bucket in the basement full of small agates we found when the kids were young.
Types of Lake Superior Agates:
- Fortification Agate: most common type, colorful banding patterns that connect with like the walls of a fort.
- Parallel-banded, onyx-fortification or water-level agate: has straight, parallel bands over all or part of the stone.
- Moss agates: these have tree-branch-shaped bits of minerals embedded in them.
- Eye agate: desirable and rare Lake Superior agate, this stone has perfectly round bands or "eyes" on its the surface.
- Waterwashed agates: rare agates with smooth natural surfaces created from tumbling in the waves on a rocky beach.
- All-Timer Agates: a collector's dream agate, these agates weigh in at 2 pounds or more and have perfect shape, color, and banding qualities.
Agates are gemstone that can be cut, polished and used in jewelry or, in the case of larger agates, for display. Not all agates found in Minnesota are of gemstone quality. The freezing and thawing to which they are subjected often causes fractures in the agates.
There are three techniques that can be used to cut and polish agates:- Tumbling: this most common technique can be used with small agates. The stones are rotated in a rock tumbler with polishing grit to achieve a smooth and shiny surface.
- Diamond saw: used to cut medium size "laker" agates into slabs. The slabs can then be cut into artistic shapes--called cabochons--polished, and used in jewelry or artwork.
- Face polishing: involves polishing a curved surface on a part of the agate while leaving most of the agate in its natural state.
What Does an Agate Look Like?
The rocks and stones we find on the beach won't look much like the ones we find in shops that sell agate jewelry and art items. So, how are you to know what to look for? If you want to be a serious agate hunter, I would suggest you buy a guide book to agate hunting. Two of the best can be found on this page.
Here are some basic clues to finding the Minnesota State Gem:
- The color band planes where an agate is chipped or broken are sometimes visible, giving the rock a "peeled" texture.
- Iron-oxide staining is found on nearly all agates and often covers much of the rock. The staining can most commonly will be shades of rust-red and yellow.
- Translucence is an optical feature produced by chalcedony quartz, the principal constituent of agates. The quartz allows light to penetrate, producing a glow. Sunny days are best for observing translucence.
- A glossy, waxy appearance, especially on a chipped or broken surface, is another clue.
- The surface of the rock is often pitted texture.
Other Place to Find Agates
The shores and beaches of Lake Superior are not the only places to find agates.
The Superior glacier lobe spread agates and other debris throughout northeastern and central Minnesota. Hikers, campers, hunters, and outdoor enthusiasts can readily collect them in many parts of the state...even right in the Twin Cities.
Here are some of the places where you can keep a sharp eye out for Minnesota agates:
- Along the Mississippi River and waters that empty into Lake Superior all along the North Shore.
- Along walking paths or trails in a wide swath from the North Shore to the Twin Cities.
- In the river rock that is used for landscaping around many business buildings.
- Farm fields in the spring or after a hard rain. Ask permission of course.
- Gravel pits and quarries if you can get permission to agate hunt in them.
- Virtually any place with exposed gravel and rocks offers the chance of finding agates.
More Agate Resources:
A Lapidary Guide to Lake Superior Agates
Article about Agates and Geology of Lake Superior
Moose Lake Agate Festival
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Lake Superior Photos, Memories and Stories
Minnesota's Lake Superior region is one of our favorite vacation spots. It is also one of the most beautiful places to pose for great photos. Share your Lake Superior stories, memories and photos to help other visitors to Minnesota find those "not to be missed" vacation spots along the North Shore. Share photos of fall foliage, or photos of Lake Superior gripped in a winter storm. We want to see them all!
Related Pages:
Lake Superior North Shore
Lake Superior Circle Tour
Lake Superior Lighthouses
Lake Superior Vacation Rentals
Scuba Diving Lake Superior
Lake Superior Fishing Charters
Lake Superior Ice
Duluth Minnesota Vacations
Minnesota Water Trails
Share Your Lake Superior Photos
Minnesota Vacations at TripAdvisor
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