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Calling all rockhounds! Thunder eggs are some of the most beautiful rocks you can find, kind of like surprise packages from the earth! Before you head out hunting, let’s learn how to identify these hidden treasures.
Thunder eggs are usually about the size of a baseball and have a hollow center filled with colorful minerals like quartz, opal, jasper, or agate. But you won’t know what’s inside until you crack one open! These beauties can be found in several US states, including Idaho, Oregon, and California. Look for them in streams and hillsides.
Let’s take a look at how thunder eggs form, where they can be found, and which states in the United States are best for finding them!
If you want to check out the best rock and mineral identification books, you can find them here (Amazon link).
Where to Find Thunder Eggs Near Me (Most Common Environments)
Thunder eggs are like geodes, but they’re usually completely filled with colorful minerals instead of just partly filled. This difference is all thanks to how they form.
Thundereggs only come from volcanic ash. As the hot lava cools and hardens, trapped gas bubbles form inside. Over millions of years, minerals slowly fill these bubbles, creating the beautiful treasures we know as thunder eggs.
The best places to hunt for thunder eggs are areas that once had volcanic activity, like creeks, hillsides, canyons, mountains, and rocky outcrops.
Let’s analyze some of these mediums and see why they are the best for finding thundereggs!
Creeks and Hills
Thunder eggs are typically found in creeks, hills, rivers, and streams. Thousands of years of geologic activity carried them away from their original formations. Rhyolite, the volcanic rock from which they form, is also common in these areas.
Although it is difficult to tell the difference between a thunder egg and a regular rock, slicing one in half with a lapidary saw will reveal whether you have found what you are looking for.
Mountainous Areas
The high elevations of mountainous areas often reveal various exciting rocks and minerals. Thundereggs were often found in such regions, especially if creeks were also present.
Outcrops
Rocky outcrops bring forth many interesting rocks and minerals from below the ground. You can even find thundereggs in such mediums, but they are rare. It all depends on the state’s past geologic history. In Oregon, for example, you can find thunder eggs in various outcrops.
TIP: Both geodes and thundereggs look like ordinary stones from the outside. Check out the main differences between these two similar rocks in the article below:
The 7 Main Differences Between Geode and ThunderEgg
BTW: Do you want to know more about rock and mineral identification? The books listed below are the best ones you can find on the internet (Amazon links):
- Smithsonian Handbooks: Rocks & Minerals
- Gemstone & Crystal Properties (Quick Study Home)
- Ultimate Explorer Field Guide: Rocks and Minerals (National Geographic Kids)
Where Can I Find Thunder Eggs in the USA? The Best Locations
Thundereggs are found throughout the world and in many U.S. states. Even if you aren’t located in the states mentioned here, that doesn’t mean you shouldn’t look for thunder eggs in the environments mentioned above, especially if your state has a rich volcanic history in those regions.
Oregon is the best state to find thundereggs in the U.S., where several rock-hounding locations are available for enthusiasts to collect these volcanic rocks at will. The other great states to find thunder eggs in the U.S. include Idaho, Oregon, California, Arizona, Washington, and New Mexico.
| State | Locations |
|---|---|
| Oregon | Jefferson County, Harvey Creek, Whistler Spring |
| New Mexico | Little Florida Mountains Mining District, Luna County |
| Washington | The Little Naches River Bed, Yakima Town |
Even if you strike out searching for thunder eggs on your own, there’s still hope! Rockhounding clubs are a great resource. These groups often know the secret spots to find all sorts of treasures, and you might even make some new friends along the way.
Now, let’s dig into some specific states and see where you can find those amazing thunder eggs!
Oregon
Oregon is like thunder egg paradise! It’s the only state where thunder eggs are the official rock, and there are tons of places to find them. Here’s a look at some popular spots:
- Central Oregon: This is a great place to start. The Ochoco National Forest near Prineville and Madras has great hunting grounds. You can also find thunder eggs at Succor Creek Canyon in eastern Oregon.
- Free and Paid Sites: The good news is there are plenty of free public areas in Oregon where you can search for thunder eggs. But there are also pay-to-dig sites if you want a more concentrated area. Some popular free sites include Ashwood, Willowdale (known for geodes, too!), Sunflower Flat, Harvey Creek, Forked Horn Butte, White Fir Spring, White Rock (known for opals and agates, too!), Whistler Spring, and Desolation Canyon.
- Eastern and Southern Oregon: Crane Mountain, the west flanks of Hart Mountain near Warner Peak, and the eastern side of Steens Mountain are all good hunting grounds in these regions. You might also find quartz crystals and opals in these areas.
- Keep Exploring: Even if these spots aren’t close by, remember that most hills and creeks in Oregon, especially Crook County, are worth exploring for thunder eggs.
Tip: Oregon offers the best of both worlds – free public digging areas and pay-to-dig sites for a more concentrated search!
Idaho
Idaho has various interesting volcanic rocks, minerals, crystals, and fossils. Thundereggs are also found in this state. Thundereggs are most commonly found in the state’s southwestern regions.
It would be best to go to Hog Creek, near Weiser. It is the best thunderegg spot in the state, with enthusiasts able to find stunning amethyst thundereggs throughout the region. Geodes and thundereggs can be found in numerous locations throughout Southern Idaho.
Antelope Creek, for example, is a great place to find these stunning rocks. The area surrounding Antelope Creek is vast and full of exciting specimens to collect. If you plan to visit this location, bring a lapidary saw.
TIP: Check out this article for a complete rockhounding guide in Idaho.
California
California is home to many interesting rocks and minerals, but you can also find thundereggs here. San Bernardino County is the only place where thundereggs were unearthed in this state.
If you visit this county, head to Lead Pipe Spring. Here, on the north side of the hill near Lead Pipe Spring, you can find thundereggs, opals, jasper, and beautiful blue agates. The Black Agate Hills Geode Bed in the southern part of the state also hosts some more thunderegg formations.
California has other thunderegg spots, but the best way to find them is by joining a rockhounding club or exploring other regions in San Bernardino County.
TIP: Check out this article for a complete rockhounding guide in California.
Arizona
Arizona is famous for its wulfenite, copper, turquoise, and petrified wood. However, there are some beautiful thunderegg specimens here as well. If you visit Cave Creek, you will quickly realize that it is one of the best rock-hounding destinations in the state.
Thundereggs are not the only rocks and minerals found here; jasper, quartz, agate, and even precious metals are also present. Thundereggs are commonly found on quartz outcrops in this region.
TIP: Check out this article for a complete rockhounding guide in Arizona.
New Mexico
New Mexico is, without a doubt, a prosperous state for rockhounding, and if you can visit this state, there is a great spot where you are guaranteed to find something interesting.
At the Florida Mountains, in southern New Mexico, near the town of Deming, there is the well-known Rockhound State Park.
Here, rockhounds from many regions gather to explore the many wonders they can find easily, including thundereggs, jaspers, geodes, quartz, or perlite. This state park is among the few where the collection is permitted and supported.
TIP: Check out this article for a complete rockhounding guide in New Mexico.
Washington
The state of Washington has a couple of Thunderegg collection sites. For example, the Little Naches River bed, located just northwest of the town of Yakima, has plenty of high-density thunderegg sites on public lands.
Washington also has some great spots for finding thunder eggs! Here’s a quick guide:
- Little Naches River: This is a popular area where you can find thunder eggs along with other rocks, minerals, and crystals. Make sure you check the regulations for collecting in this area.
- Western Washington: Look near First Creek and Green River for thunder eggs.
- Mount Baker: Head to Blue Lake, Rainbow Falls, or Swift Creek for your thunder egg hunt.
- Mount Higgins: This area has several spots known for thunder eggs, including Creek Crossing, K-Jay Bed, Iron Gate Point, Pine/Milk Creek, Rim Rock, and White River.
Remember: Always check local regulations before collecting rocks and minerals on public lands.pen_spark
TIP: Check out this article for a complete rockhounding guide in Washington.
TIP: Thundereggs form in layers of different types of stone. This geometry makes it likely that the egg will break along the layers rather than along the middle when hit with a chisel. Find out how to cut and polish thunder eggs correctly in the article below:
How to Cut & Polish Thundereggs: Follow These 6 Simple Steps
FAQ About Finding Thunder Eggs
Still did not find the answer to your questions about finding thunder eggs? Find frequently asked questions in the section below:
What Do Thunder Eggs Look Like on the Outside?
Thundereggs are sometimes tricky to spot. They are nodule-like rocks. However, if you observe a white-gray to reddish-brown rock, chances are pretty high that you have found a thunderegg. Now, the last thing to do is cut the rock in half with a lapidary saw and reveal its contents.
How Do You Know If You Found a Thunder Egg?
Thundereggs often have brown-gray exteriors, and they are abnormally round. They are about the size of a baseball but can get larger. If you find a soft-mud-like or clay-like ball, cut it in half. Chances are high that you have found a real thunderegg.
What States Have Thunder Eggs?
Not all U.S. states have thundereggs. Those include states like Idaho, Oregon, California, Arizona, New Mexico, and Washington.
Thundereggs may also be present in other states, but the best way to tell is to join a rockhounding club or explore the environments in which thundereggs are commonly found.
BTW: If you are looking for the best UV light for rockhounding, find out my picks below (Amazon links):
- BEST OPTION: Convoy 8+ 365nm UV LED Flashlight with Patented Glass Filter
- BUDGET OPTION: Karrong Rechargeable 1200 Lumen 395nm UV Flashlight
- OPTION FOR INDOOR USAGE: Prime Upgraded Big Chip 396nm UV
Conclusion
Thunder eggs are like nature’s surprise packages! They can be just as beautiful as geodes, sometimes even more so, with all sorts of colorful minerals inside. And the coolest part? Every single one is unique!
Ready to hunt for these hidden treasures? The key is knowing where to look. We’ve talked about how thunder eggs form and where to find them in some states, so check out those sections to plan your next adventure. Happy hunting!
TIP: There is more to rock tumbling than just following manual instructions. Check out the simple and clever tips and tricks for rock tumbling in the article below:
13 Clever Tips & Tricks For Rock Tumbling You Should Know