Out of the Tumbler

Beach Cobbles, San Simeon, CA

As I posted back in March, I spent a pretty mind-blowing day collecting on the beaches near San Simeon, California, on my way up the coast. Why was it so great?  Because nearly every rock on the beaches there is of something interesting, whether a brecciated jasper, or an interesting agate, or some things that I don't even know the names for. But whatever they are, they have loads of color and striking patterns and polish beautifully in the tumbler.

They do especially well in the tumbler since they are already well-rounded by the wave action. In fact, I usually skip the first coarse grit step in the polishing process and go directly to the finer 120/220 silicon carbide.

I'm still processing rocks I found months ago, and by the time I'm done, it'll be time to head South again to find some more!

Area 54

Misc. Jasper & Agate, Area 54

Some rockhounding locations are in the guidebooks. Others are not, either by the author's choice, or because they are new locations, found just as others are exhausted by hundreds - if not thousands - of collectors.  This place was not one I'd ever read about, except on a rockhounding club website. I don't know where it got it's name - Area 54 - but it does give the place a sense of mystery: it sounds like there should be aliens or UFO's around.  All I can say is, I didn't see any...

The truth is, I don't know exactly where Area 54 is, or at least where the club trips go. It is somewhere on the road into the Panoche Hills in Fresno County, California. I never found the exact spot they described, but it doesn't matter. You can look anywhere in a 5 mile radius, or anywhere along that road and you will find colorful, sometimes stunning, material. The pieces I've posted here just came out of the tumbler - but I have much more.

My advice?  Next time you're driving south on I-5 in central California, take a short detour and explore this canyon.  You won't be sorry!

FOLLOW-UP NOTE: June 15.  I've finally gotten these stones all the way through the polishing process, and sadly, they don't polish well. Most have a largely matte finish with only a few seams that took a good polish. I might have worried that I had done something wrong in the process (such as contaminating the batch with heavy grit somehow) but there were a few agates from elsewhere in the batch and they took a perfect polish - so I know it's the stones. So if they are jasper, they are a somewhat softer one.

Revealed

I am slowly working through the rocks I collected in southern California last month, including some interesting jaspers from the Central Coast. One of my favorite locations, as I have mentioned before, is the stretch of coast between Cayucos and San Simeon. Some of the most colorful, varied, and spectacular jaspers I have ever found were here, a place I am sure to go back to again and again.

Sometimes, I pick up rocks that show very little on the outside, maybe a little color, or the glassiness  of agate or jasper. I don't remember what I saw with this one. It was yellow overall, with the smooth sheen of jasper, but very little patterning on the surface.

Today I cut through it revealed a wonderful variety of patterns, almost like the "Picture Jaspers" I look for every year in the Owyhee canyons of Eastern Oregon.  These are the two cut ends of the same piece, about the size of my fist.  Wonderful.

Cayucos Jasper

Brecciated Jasper

I'm still poring over the 100 lbs of stones I brought back from California last week (the back of my car riding very low). I had a chance to cut open some of the larger pieces, many of which are of a  brecciated jasper that is common in this part of the Coast range (and several other parts of California).  This one is about 8" inches across and shows a fractured yellow-red jasper with a milky quartz filling.

Not a great picture, I admit, but you get the idea. Not sure how the quartz will polish, but we'll give it a try.  The diversity of the rocks along this coast is truly remarkable.  I suggest walking up Toro Creek near Cayucos, or for the best material, head straight to San Simeon Beach. Wow.

Going Crazy in California

San Simeon Jaspers - Naturally tumbled

I do a lot of beach-walking around the Northwest where I live, and often find intriguing and worthwhile rocks mixed in with a lot of junk. So you can imagine what a kick it is to stumble on to a place where nearly every stone is colorful, and beautifully patterned. I had heard about the brecciated jaspers of San Simeon Creek, near Cambria, California and seen some beautiful examples (see Hans Gamma's mouth-watering collection ) but nothing prepared me for a walk along the surf-line yesterday. It was like walking through a kaleidoscope...  In less than an hour I had filled up two cloth bags, and I could have spent days there, seeking out the perfect specimens.

an iPhone sample

The location is the small beach area just south of the San Simeon State Park campground. It's only a quick scramble down the slope and out to the beach. Most of the rocks on the beach itself were tumbler-sized. I'm guessing the big specimens must be somewhere up in the Coast Range headwaters of San Simeon Creek and others. But there are also loads of medium-sized rocks (e.g. 1-4 pounds)  up high on the beach, but I didn't have time to carefully go through them. I'll bet there are some winners there.

But for anyone whose idea of a perfect day is to walk along a wild Pacific beach picking up beautiful stones, you would have a hard time finding anything better than San Simeon.

Beach Surprise : "Plume Agate?"

Beach agate, West Seattle

It's been a while since I was out on the beaches near home - blame it on cold weather and too many buckets already full of rocks, waiting for the polisher.

But on a handsome sunny winter day, I hit the beaches near Alki Point. I am always attracted by color and design, but especially if there is any sense of transparency, e.g. that glass-like quality that suggests "agate."

Here's one I found yesterday, an already well-rounded, naturally polished agate. My first thought was that it was what is known as a plume agate, in which impurities grow into the quartz often in lovely, lacy patterns. But when I took a close look at this, it does not have the typical "plume" patterns, but instead appears to be some sort of brecciated rock into which quartz has filled the gaps. Hard to tell what the green stuff is, but it's clearly fractured and shattered. Now, of course, it is suspended in the quartz matrix. Not sure what to call it, but it's handsome nonetheless.

California Treasures

Cayucos Jasper, California

In a post a few weeks ago, I reported that I spent a wonderful few hours exploring the beaches near Cayucos, California, in what turned out to be a mother lode of jasper of every pattern and description. Many were so beautifully rounded that they needed little tumbling, and just the addition of a polish to make them stand out. Well, I finished a batch today - and they are beauties.

There are brecciated jaspers (apparently common along in coast range in this area) and a variety of other colors and patterns. It was probably the single most productive few hours I've ever spent chasing rocks.

Having said that, the beach is NOT the best place for collectors looking for slab-worthy chunks of the stuff - these are all small, and really only fit for those who are content with tumblers. I am one of those, and I am delighted with what I found.  Too bad it's a thousand miles south of here!

Polisher Preview

Cayucos Jasper, CA

Here are two early pieces of the Cayucos Jasper from the Central California coast I found earlier this month (see below) An astonishing diversity of color and pattern, found within just a few yards of the beach. Definitely a place worth going back to.

Mystery Solved...

Brecciated Cherts, Channel Islands, CA

I collected these stones along the shore of Santa Cruz Island in California's Channel Islands last year. They were obviously silica-rich and took a nice polish, but were structurally all over the map: some were clearly banded like a conventional sedimentary rock, while others were fractured and chaotic.  I collected a dozen or so, but could not seem to find out what they were.

Then, recently, I struck up a conversation with a California geologist, who turns out to have done his PhD on the rocks of the Monterey Formation and immediately identified these as nice examples of brecciated cherts from the Monterey!   I still haven't figured out the exact mechanism of their formation, but they are pretty unusual in any case.