Clear Creek plasma agate is an incredible formation of dozens of minerals, creating a kaleidoscopic whirlwind of colors. This material is all collected from one place, but it’s open to the public for those dedicated rockhounds looking for a specimen.
So, let’s dive in and we’ll talk about what plasma agate is, where you can find it, and even some tips on cutting this beautiful lapidary material!
Read More: Agates: Ultimate Guide To Collecting Agates
What is Clear Creek Plasma Agate?
Clear Creek’s plasma agate is a bit different. It’s a conglomerate of a bunch of different minerals, ranging from jadeite to cinnabar to chalcedony. These minerals are pressed together in a way that creates a spectacular display when cut.
This conglomerate is often cut into fantastic cabochons for both collectors and jewelers. The material can vary massively even in the same nodule, creating individual displays of nature’s beauty.
The stuff is pretty. It’s not a true agate but the various forms usually include plenty of clear, white, and blue chalcedony binding them together. The best material will have a high chalcedony content, which keeps it from crumbling during processing.
The material is all mined from the Clear Creek Management Area in California.
Not to be confused with the Clear Creek Recreation Area, which is in Alabama but often referenced when online information about plasma agate is sought after.
This area of land is under BLM management and you’ll need a permit to visit and collect material. There’s a lot more than just plasma agate in these hills, it’s worth a trip for any California-based rockhound!
The area was actually closed for eight years, starting in 2008, due to concerns about natural asbestos in the area. It’s not clear whether this was a false alarm or a passing hazard from the information readily available.
Occurs In Good Amounts
What is known is that this fantastic conglomerate occurs in good amounts. BLM permits allow for collecting in a “reasonable manner for personal use.” Most collectors seem to bring home between 50 and 100 pounds of material, but stick with what you consider reasonable.
The stone’s hardness and exact composition vary a lot, and it won’t reveal its true nature until it’s cut.
The stone’s exact makeup varies widely across the area. Some samples are mostly blue and green with white streaks, while truly fantastic material occurs with a range of colors from purple to transparent.
The larger areas with great material are jealousy guarded by collectors, but the good news is that great material can be found by anyone with some time and a good eye!
Field Collecting Tips
Collecting this material is similar to collecting any other agate. You’ll be most likely to find it in the creek, although the material has been dug up in other locations.
For instance, stones with red coloration are more likely to occur in zones closer to the local mercury mine. The red speckles are comprised of cinnabar after all.
I recommend bringing a rock pick at the very least, but a folding shovel and some hammers and chisels aren’t a bad idea at all. You may want to dig in some cases.
Where to Focus Your Attention
For someone with no inside knowledge of the area, the best bet is to follow the creek. The stones are easier to recognize when the creek is running due to their multi-colored “skin.” Don’t ignore dry land either: you can often find good pieces higher than the water level.
How To Spot Plasma Agate
Identifying the stone can be hard for beginners. My best advice on this is to look over as many pictures of rough as you can find. The stone hasn’t quite caught on enough for galleries of rough nodules to be common, but digging through pictures on eBay, Etsy, and other sites will help give you an idea of what it looks like.
Wetting the stone will help identify it as well.
Pay Attention To The Weather
This area gets pretty hot in the summer, so plan your trip accordingly. It’s still not as rough as a lot of rockhounding in California, where desert conditions frequently make mining a strenuous affair. It still won’t be easy.
Likewise, here’s a hint from a lifelong California rockhound: try not to get out there just after a rain. Most areas in the state are beautiful for a couple of weeks following rain, but in a lot of places, it also turns the ground into terrible mud.
This area is no exception. Give it two to three days after a rain if time permits.
The Area is Not Well Documented
The Clear Creek area isn’t well-documented for the most part. There are a ton of mines for different materials, a lot of rare minerals, and it’s generally a rockhound paradise. The problem is that a lot of the information isn’t documented and the area is large and covered in dense vegetation.
If you don’t have anything specific in mind, I strongly recommend starting along the creek and any attendant streams. Once you’ve developed an eye for the skin, you’ll be surprised at how often you find the material.
Not All Specimens Are Keepers
Another thing to keep in mind is that not every plasma agate nodule is a winner. Conglomerates are unpredictable and this material is known for being crumbly and having undetectable soft patches you can’t see from the exterior of the stone.
That’s also something to keep in mind if you’re planning to buy rough online. Someone with a lot of experience in the area may be able to tell you that pieces are mostly solid, but there’s no 100% guarantee you’ll have great material.
Cutting Tips for Plasma Agate
Plasma agate can be a bit tricky to cut for a newbie. Keep that in mind if you’re planning on slabbing and/or cabbing the material you’ve collected.
The main issue is just that a lot of the stone is crumbly. This is a common problem with conglomerate material, but low-grade plasma agate may break up before you can even make an exploratory cut.
There can be crumbly pockets in an otherwise solid chunk as well.
Don’t get too attached to any bit of plasma agate until you’ve slabbed it. After being slabbed, you’ll be able to work around pockets of material with fractures, cracks, or that just didn’t form a strong enough conglomerate.
Likewise, it’s important to trace out any cabochons you’re cutting by keeping in mind the soft patches.
Plasma agate cuts like most agates, but it has a tendency to “orange peel” since many of the minerals are of different hardness. Lighter pressure than normal on the wheels helps, but you may want to use some sort of crack-filler if the piece won’t cooperate.
Lastly: always wear a mask when cutting plasma agate. The exact mineral composition of each piece is different, but a few of the minerals it can contain, like cinnabar, are more toxic than the usual silica dust.