Lake Superior Agates are prized by collectors for their vibrant concentric banding caused by iron impurities deposited in gas cavities within ancient basaltic lavas. These are typically found in glacial gravels and along the shorelines of the Great Lakes, recognized by their smooth, pitted surfaces and translucent, multi-colored layers.
Is this lake superior agate?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch lake superior agate with a known reference. Lake Superior Agate sits at Mohs 6.5-7 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Lake Superior Agate leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Lake Superior Agate typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: red, orange, yellow, white, brown, gray.
- 5Look at form & habitCrystal system: trigonal. Typical habit: banded nodules.
Often confused with
Lake Superior Agate vs. its common look-alikes — and how to tell them apart in the field.
How to tell apart: Luster reads vitreous on Lake Superior Agate and waxy on Jasper.
How to tell apart: Luster reads vitreous on Lake Superior Agate and waxy on Flint Nodules.
How to tell apart: Luster reads vitreous on Lake Superior Agate and vitreous to waxy on Carnelian.
Often found alongside lake superior agate
Minerals reported to co-occur with lake superior agate. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- SiO₂
- Mohs hardness
- 6.5-7
- Density
- 2.6-2.7 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Trigonal
- Crystal habit
- Banded Nodules
- Cleavage
- None
- Rarity
- Common
- Uses
- Lapidary, Collector, Decorative
- Host rock
- Glacial Drift and Basaltic Lava Flows
- Typical price
- $5-50 for small nodules, higher for large, high-contrast specimens
Where rockhounds find lake superior agate
53 mapped spotsClassic worldwide localities
- Minnesota
- Wisconsin
- Michigan
- Ontario
- Lake Superior region
U.S. states with lake superior agate
Each link opens a state-specific list of mapped rockhounding spots that produce lake superior agate.
Field-hunting tip
Look in glacial drift and basaltic lava flows country — that is the host setting where lake superior agate typically forms. If you start seeing quartz, goethite, hematite in float, you are in the right ground. Field specimens usually show a banded nodules habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Minnesota, Iowa, Wisconsin — start trip planning there.
More lake superior agate photos
Common questions
How do you identify lake superior agate?+
Where is lake superior agate found?+
Can I find lake superior agate in the United States?+
How much is lake superior agate worth?+
What rocks look like lake superior agate?+
What minerals are found with lake superior agate?+
What kind of rock does lake superior agate form in?+
What is lake superior agate used for?+
Find lake superior agate on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
