North of Madras, Oregon, you’ll find giant thundereggs tucked away on a hilltop near the ghost town of Ashwood. Polka-dot agates and thundereggs occur naturally at the Priday Polka-Dot Agate Beds.
The thundereggs you’ll find here are amazing! You never know what kind of treasures you’ll find on the inside.
I was impressed by the layered, colorful rock formations alongside the road on the drive to the site.
When we arrived, we were told where to dig and what to look for. The staff were friendly and knowledgeable about the local geology. Samples of rough, and cut and polished rocks were on display.
We asked if it was okay to bring our dogs while digging. They said we could and admitted to liking dogs more than some people. 😉
Giant thundereggs galore!
We brought our own rock hammers and bags, but they provide them for free. I noticed they had five-gallon buckets for collecting rocks and soon learned why. There are HUGE thundereggs here! I put a ruler into the picture below to show the scale of rocks we collected.
Some of the thundereggs at the Priday Polka-Dot site have mini stalactite or stalagmite-type formations inside. Collectors are fond of this type of thunderegg.
We both worked on prying thundereggs free from the substrate. It’s not easy work, but recent rainfall loosened the soil.
I always look at the rocks other visitors cast aside. You can find real treasures in these piles!
We had a couple of our finds cut in half. There’s a small charge for this service, but it’s worth it.
Just a reminder… rocks are HEAVY! They charge $2.00/pound for the thundereggs. I like rocks a lot so I thought it was worth the price.
We’ve collected thundereggs at Richardson’s Rock Ranch, south of here, several times, but the thundereggs at the Polka-Dot site are much bigger. Richardson’s no longer allows public digging, but it’s a good place to get extra-large thundereggs cut. They also have an excellent rock shop, including rocks with origins from all over the world for purchase.
Other rocks for sale
You’ll see large piles of various types of rocks for sale near the parking area at the Polka-Dot mine.
The polka-dot agate mine near the thunderegg site was not open for digging during our April 2022 visit. There’s a huge boulder of polka-dot agate near the cutting area and small samples nearby you can buy.
I bought a small piece to bring home. Black, brown, and red polka-dots are scattered across a white or light blue base on these agates.
The Priday Polka-Dot Agate Mine also has fire opal for sale but I misread the sign as $2.00/pound when it’s actually $200/pound. Ooops! Here’s a small faceted piece from a mine in southern Oregon that I purchased a while back on eBay. The Juniper Ridge fire opal mines are privately owned and there’s not currently a dig site open to the public.
Check the West Coast Mining website for operating hours or call ahead to make sure they’re open.
To get to the mine, drive 15 miles north of Madras on Highway 97. Look for the sign to Ashwood and head east nine miles on a winding, scenic road.
You’ll know you’re at the right spot when you see the polka dot-painted trailer.
An added bonus
When we were there in late April, we were happy to see one our local wildflowers in bloom. The magenta blossoms of the snowball cactus were beautiful!
We will visit the Priday Polka-Dot Agate Beds again in the future. It’s a wonderful site to find incredible giant thundereggs – and our dogs had fun too. 😀