Southern California is enormous and home to many different varieties of rocks and minerals. Among the most popular stones found in this region are agates, which show up in a ton of different varieties scattered throughout the entire Southern portion of the state. For those who are looking, it’s important to make sure you hit the right spot.
So, let’s take a look at where to find agates in SoCal, and I’ll give you some field-tested tips on digging them out
Related: Ultimate Guide To Collecting Agates
1. Jalama Beach
Jalama Beach is just one of the many beautiful beaches that are scattered along the Southern portion of the Central Coast. It’s the classic sandy beach, sitting underneath chalky limestone cliffs, and a popular destination for surfers. The beach itself can be accessed from the highway just south of the small city of Lompoc, on a windy road that leads down to the beach itself.
Jalama’s agates tend to come in two different varieties. The main one that you’ll find are known as Root Beer Agate. These are brown and white banded agates, sometimes interspersed with layers of limestone. They’re a frequent find in the area and you can find untouched nodules weathered out of the cliffs if you walk far enough. Try digging through the sheet-like limestone at the base of the cliffs.
There is also a blue-grey variety that pops up on a regular basis along the shore. These seem to come from an off-shore deposit and come up with the surf. Some are a bit undistinctive, but many bear interesting patterns or colors as well. Combined, these two varieties make for an interesting rockhounding experience and there are certainly other, rarer, varieties that also appear.
2. Bullion Mountains
The Bullion Mountains of the California Mojave bear a lot of minerals. Of prime interest to collectors is the variety of agates that appear, including some truly spectacular and rare strains of the cryptocrystalline stones. Access will require a capable vehicle, or more than 10 miles of desert hiking, but the mountains are located inland of San Bernadino and north of Joshua Tree National Park.
Keep in mind that this is desert rockhounding, and you need to be able to take care of yourself if you head out there. Help is not nearby if someone in your party gets dehydrated or suffers from a heat-related condition. Water, food, and possibly extra fuel if you use an off-road vehicle should all be brought along with you. The mountains themselves are host to a variety of minerals spread across the small range.
The main draw here is the rare Bullion Mountain Plume Agate. While some of California’s agates are a bit muted, these plume agates are incredibly bright, multi-colored, and have a high-transparency that lets you stare deep into their inclusions. They’re among my favorites, and they’re sure to be one of yours if you have the fortitude to make the trip.
3. Turtle Mountain
If you don’t have the vehicle to make it out to the Bullion Mountains, you’re not out of luck. About 45 miles inland of the end of the Bullion Mountains lies Turtle Mountain. On the banks here are a couple of distinctive agate types that define the area. As with the rest of the mountains of the Mojave Desert, you’re also not limited to just agate here and there are other minerals present.
The two forms which occur here couldn’t be more different. The more common find is botryoidal chalcedony formations. These are “white” agate, banded around the different spheres that make up each individual chunk. Some of these are UV-reactive, glowing with an intense green light when exposed to UVB in the proper wavelength and they make great display specimens.
The other, rarer, form here is a brightly colored, sagenite-included agate. While they superficially resemble petrified wood when sliced (and it does occur out here occasionally) it turns out that it’s actually a pseudomorph of another mineral. These agates have replaced old barite or calcite crystals, giving them the appearance of a starburst when cut open. It’s really cool stuff, especially when it has brighter colors.
Nipomo is a small town between Santa Maria and Arroyo Grande on the 101. It’s actually the town where I grew up and developed my love of stones, and it all boils down to the variety of agate named after the place. It’s not a popular destination for people driving through, but in the clay soil on the Eastern end of town lie some beautiful stones.
The main variety of interest is an orange chalcedony with included plumes of marcasite and sagenite. The silver and black is rather distinctive when mixed with the strangely-colored chalcedony and it’s a great find. I had dozens of them tucked away when I was a kid, never knowing that they were actually named for the town.
These agates generally require a bit of digging unless you’re in the right spot after one of the rare rains the area gets. Finding a spot to dig is generally the hardest part if you don’t have access to private land. Fortunately, it can also be found in some parts of the Los Padres National Forest accessed off the backroads on the Eastern end of town.
5. Waterways and Riverbeds
I can’t stress enough that large portions of Southern California are filled with jasper and agate types. Waterways and riverbeds are my favorite places to hunt no matter where I am, and that love comes from spending time in Southern California’s dried-out riverbeds. The perpetual drought that plagues Southern California also means that there are miles and miles of perfectly dry riverbeds to walk no matter where you are.
Types vary based on location. Most of my favorite hunting grounds cut through the Franciscan Assemblage at some point. While normally associated with the Bay Area, these rocks peek up in portions of SoCal and you can identify the areas easily. Franciscan Chert is a constant in these areas, which is a red cryptocrystalline silica formation that’s often streaked with white chalcedony. Anywhere it can be found, there’s a good chance of digging up some impressive jaspers and agates.
But you don’t need to be in one of those areas to find great stuff. Find one of the larger riverbeds, such as the Santa Ynez Riverbed, and start walking until you find a spot where dense rocks are piled up. Dig through these piles and you can find all sorts of treasures, just bring a large bag along!
One thing to be aware of: these riverbeds also host a few nasty critters. Rattlesnakes and Black Widow Spiders are the main concern. Avoid piles of wood, any grass taller than a couple of inches, and journies through the chaparral whenever possible. I’m sure people have been bit while out rockhounding but it’s a rare possibility, just something to be aware of when you’re trekking.
The beaches of California are generally amazing places to find agate, jasper, and chalcedony. They’re also a great way to spend the day, particularly if you’re not a local. The varieties vary from beach to beach but there’s a large variety of them to be found. In particular, the rocky beaches around Santa Barbara such as Refugio Beach or El Capitan host some spectacular agate.
Beachcombing for agate is one of the easier forms of rockhounding. You can simply walk the beach in many places and find them along the surf when the tide is going out. The other thing to keep an eye on is the cliffs. In some places, the limestone or shale has left behind nodules as they’ve eroded, and you’ll see small piles of stone at the base of them. Dig through these when you find them, you’ll be pleasantly surprised.
The best beaches are those which have areas where geological zones meet, but most will yield at least a few choice selections. You’re unlikely to be the only one looking, so getting farther away from the parking lot or getting into areas that require a bit of extra fitness are your best bets.
Just be careful if you choose the latter route. While there are climbable cliffs in many areas, the sedimentary stone that makes them up is also crumbly and gives way easily. I’ve also seen a few newbies trap themselves on beaches by going too far when the tide has been coming in. The ideal time to hunt is when the tide is beginning to go out.
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