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On the Oregon–Idaho border, near the little town of Nyssa, lies one of the most famous agate collecting sites in the Northwest: Graveyard Point. For over a century, this area has produced agates filled with striking “plumes” — delicate, featherlike inclusions of minerals that look almost like smoke or underwater plants frozen in stone.

The Setting

The Graveyard Point area is open, sagebrush country, cut by dirt roads and ranch land. Collecting usually means digging in claims or searching tailings piles left behind by earlier work. Some areas are under active claim today, so it’s important to know where you’re allowed to collect. A lot of people visit through fee-dig operations or purchase rough from local dealers who work the ground legally.

What You’ll Find

The agates here are known worldwide for their plumes. These inclusions can be yellow, brown, white, black, or even reddish, and they often appear suspended in clear or milky purple chalcedony. Good pieces polish beautifully and are prized by lapidary artists for cabochons and jewelry. The best material shows intricate branching plumes with strong contrast against the agate background.

The Collecting Experience

Digging for plume agate isn’t light work. Nodules and seams are buried in hard rock, so collectors often use picks, chisels, and sledges to break open the ground. Even then, not every piece is a keeper — just like with thundereggs or petrified wood, you’ll go through a lot of ordinary rock to find the special ones. Still, the chance of uncovering a piece of world-class plume agate keeps people coming back.

Why It’s Special

Graveyard Point has a reputation for producing some of the finest plume agate in the world. Many agate beds exist across the West, but few show the same level of clarity, pattern, and variety. The material has been collected and sold for decades, yet it still turns up in shows, shops, and private collections as some of the most desirable agate available.

Things to Keep in Mind

• Access: Much of the land is claimed or private. Always check before digging, or use fee digs where available.
• Tools: Strong hammers, chisels, and pry bars are often needed for serious collecting.
• Heat and dust: The desert setting means hot summers and dusty roads—bring water, sun protection, and plan for rough conditions.
• Buying rough: If you can’t or don’t want to dig, Graveyard Point plume is widely sold as rough or slabs at rock shows and online.

Closing Thoughts

Graveyard Point is more than just another collecting site. It’s a place with history, character, and a reputation that has spread far beyond the Northwest. For those who dig it themselves, the hard work makes a good find even sweeter. And for those who simply cut and polish the stone, the plumes inside speak for themselves — intricate, delicate, and timeless.

Saddle Mountain, in central Washington near Mattawa, is one of the state’s best-known spots for petrified and agatized wood. The ridge runs for miles above the Columbia River, made up of layers of basalt and ash from ancient eruptions. Over time, wood that was buried in those flows was replaced with silica, leaving behind fossils that are now dug out by collectors.

The Collecting Experience

Reaching the dig sites isn’t always straightforward. The roads are rough and dusty, and higher-clearance vehicles do best. Once you’re there, it’s a matter of walking the hillsides and prying into the breaks in the basalt. Most collectors bring shovels, chisels, and pry bars to work material loose. It’s hot and dry country in the summer, so plenty of water and sun protection are musts.

What You’ll Find

The material at Saddle Mountain is usually limb casts and chunks of petrified or agatized wood. Some pieces are simple brown or gray, but others show agate interiors with subtle patterns. A few even take a polish well enough to cut into cabochons or display slabs. The best finds are full limb sections, still showing bark impressions or growth rings.

Why People Go

Even though the site is worked heavily, there’s still a steady trickle of material for those willing to dig. Part of the draw is simply the landscape itself—the views across the Columbia Basin from the top of the ridge are wide and impressive. For many rockhounds, Saddle Mountain is a rite of passage: a place where you can spend a day breaking rocks, come home dusty and tired, and hopefully have a few good pieces of agatized wood to show for it.

Rimrock Lake, tucked into the east side of the Cascades in Yakima County, Washington, is better known as a fishing and camping destination than a rockhounding spot. Still, up in the hills above the reservoir there are deposits of thundereggs—volcanic nodules that draw a handful of collectors each year.

The Setting

The Rimrock area is rugged. Access often means leaving the road and scrambling on steep, dusty ground next to a small river. Rockhounds who make the trip usually pack light but durable tools: a short-handled sledge, a pry bar, and sometimes chisels for working into seams. It isn’t a roadside collecting site where you’ll fill buckets in an afternoon. Obtaining thundereggs here takes effort, patience, and a willingness to haul rocks back through uneven terrain.

What to Expect in the Field

Most Rimrock eggs don’t look like much on the surface. They range from fist-sized to larger nodules and blend in with the surrounding volcanic debris. A lot of the time, the outer shells break open to reveal little or nothing worth keeping. That’s part of the reputation of Rimrock—many rockhounds consider it a “high dud ratio” site.

That said, the occasional good piece makes the digging worthwhile. Some eggs contain small pockets of chalcedony or agate with soft, milky tones. Others may show faint banding or ghostly white cores that look almost opaline. They aren’t known for bold colors or dramatic patterns like you’d see in Oregon localities, but their subdued look has its own appeal. Collectors who know the area sometimes come away with a handful of keepers after a full day’s work. Colors, quartz crystals, and even druzy pockets are possible, just extremely rare.

Comparisons

If you’re used to cutting Lucky Strike or McDermitt thundereggs, Rimrock material might feel underwhelming. Those famous Oregon sites produce strong colors and intricate agate structures, while Rimrock tends toward pale interiors and less definition. But that doesn’t mean they’re without value. The eggs here show the diversity of thundereggs in the Pacific Northwest and highlight how different local geology shapes each deposit.

The Experience

For many, the draw isn’t just the rock—it’s the adventure. Collecting at Rimrock means time at the lake, quiet slopes, and the satisfaction of prying something out of the earth that few others bother to look for. When you finally cut one open and see that subtle pattern inside, it feels like a reward for the work you put in.

Things to Keep in Mind

• Be realistic: Most finds will be ordinary, and some will be empty.
• Be prepared: Good boots, gloves, and tools are essential. The slopes can be rough.
• Leave time: This isn’t a quick stop; plan for a half or full day if you want a chance at a few decent specimens.
• Respect the land: Collect responsibly, pack out your trash, and avoid tearing up more than you need to.

Closing Thoughts

Rimrock Lake thundereggs might not win beauty contests against Oregon giants, but they’re part of Washington’s thunderegg story. They offer a different kind of satisfaction—one built on effort, exploration, and the occasional quiet surprise when a plain-looking rock reveals something hidden inside. For the collector who values the hunt as much as the end result, Rimrock remains worth a visit.

For anyone who’s spent time rockhounding in the Pacific Northwest, there’s a good chance you’ve heard the name Nick Zentner. Maybe it was through a YouTube recommendation, a late-night geology rabbit hole, or a road trip podcast where his voice filled in the volcanic gaps between pit stops. However you found him, his lectures and interviews have become a kind of unofficial companion guide to the region’s wild geology—especially for those of us who like to collect a physical piece of it.

While Zentner isn’t a rockhound in the traditional sense (he’s a geologist and professor at Central Washington University), his work has had a real impact on the hobby. He connects the dots between landscapes and deep time, giving context to the strange, colorful, and sometimes frustrating rocks we dig out of the dirt. Whether you’re collecting thundereggs in Oregon, agates in Washington, or jasper in the Columbia Basin, there’s a good chance Nick’s explained the volcanic chaos that made it all possible.

Continue reading “Digging Deeper: How Nick Zentner Enriches Rockhounding in the Pacific Northwest”

When it comes to finding rocks, minerals, and especially thundereggs, few tools are more powerful (or underutilized) than Mindat.org. Built and maintained by the mineral community, Mindat is the world’s largest open mineral database—and it’s surprisingly useful for rockhounds, even if you’re not a crystallography nerd or museum curator. Whether you’re hunting agate in central Oregon or chasing copper minerals in Arizona, Mindat can help you discover spots, identify finds, and plan trips smarter.

In this post, I’ll walk you through how to use Mindat as a rockhound, with tips on reading the maps, finding thunderegg beds, and avoiding some common pitfalls.

Continue reading “Rockhounding with Mindat: How to Use the Internet’s Best Mineral Tool in the Field”

After years of digging, cutting, and collecting, I’m excited to finally open the virtual doors to Cascade Lapidary. What started as a personal obsession with thundereggs, saws, and volcanic mud has slowly taken shape into a proper outlet where I can share some of the stones and stories I’ve uncovered along the way.

This site—caslap.com—is still growing. Right now, it’s home to a small but curated selection of thundereggs and other lapidary materials, mostly from Oregon and Washington. I’ll be adding more soon: rough rock, polished cuts, maybe even some equipment and build guides if things go right. Whether you’re a seasoned cutter or just someone fascinated by what hides inside a dusty old nodule, you’re welcome here.

Check back often—there’s plenty more coming. And thanks for stopping by.