A Map of the World

Agate/Jasper, Puget Sound

Another pebble from the beaches near my home, this one reminds me of a slightly wobbly planet with golden continents surrounded by a deep blue ocean.  Hey, you've gotta have imagination.

Meanwhile, I leave Friday for a month in Brazil. No, not rockhounding, but you better believe I'll be keeping an eye out.

The Corner of the Eye

Petrified Wood,  Lincoln Park, Seattle

A walk on a beach used to be all about the view: not anymore.  Start me walking on a cobble beach, like so many here in Puget Sound country, and it's all I can do not to stare down at my feet as I walk. It's usually better to do this on my own, rather than impose my distractions on friends and family, who might wonder why I never look up...or speak...

Sometimes, it is nearly impossible to stop scouring the gravel for something interesting. In the great tradition of treasure-hunters and fishermen there is always the forlorn hope that something miraculous is about to happen: your pan will reveal a gold nugget, a massive fish will bite, or (in this case) a beautiful, unexpected stone will suddenly appear at your feet.

Consider this: there may be several million cobbles on a hundred yards of beach. So how do you train your eyes, and your reflexes, to ignore the multitudes in favor of the unique?  I have no idea. I look for bright color, of course, or a striking pattern. I'm guessing it was the latter of those that drew my eye to this thing, off to one side. No reds or blues to catch my attention, just an eye-catching irregularity that made it jump out.

There is a maxim in beach-rock-hunting : a dry rock is, by and large, an ugly rock. That's why it makes sense to patrol the water's edge, where the surf has dampened the rocks, revealing the true color and pattern of the otherwise gray shapeless cobbles that cover the beach. (You can also go on a falling tide, or better yet, a misty day.)  This one I liked it so much, even dry, that I couldn't wait for a wave, and simply gave it a quick lick - sanitation be damned!

This salty exercise revealed a small, slightly glassy agate-like stone, but with a distinctly non-agate structure.  Who knows what it is or, as always, where it originated?  But it's one I was delighted to find.

Beach Cannonballs

Concretion, Strait of Juan de Fuca, Washington

Along many of the beaches of the Straits of Juan de Fuca, these striking stone eggs (and spheres and even weirder shapes) weather out of the siltstone cliffs. They are concretions, composed of cemented sediments that grow within softer existing strata. They sometimes form around hard objects: including other stones or in the most exciting cases, around fossil animals like crabs.

I found this one (about 9" tall) on a recent trip out to the straits, and I brought it home to break open with my grandson - with the hope that it would reveal something interesting inside. The first challenge, of course, was simply breaking the thing open. After failing to make a dent with my rock hammer, we resorted to copying our neighborhood crows...and tossed it off our deck onto the street.  Bingo!

It broke, of course, but we didn't find anything obvious inside. Too bad.  Still, I'm pretty sure Theo thought the coolest part was just busting it open... 

Broken open - no Fossils

Living Opal

Ammolite chip, Canada

Ammolite is a rare opal-like gem derived from fossilized Ammonites, found only in Western Canada.  No, I didn't find this on a Puget Sound beach: it was in my mother-in-law's estate.  She was a talented jewelery-maker, and had planned to make a necklace out of this remarkable stone.

I post it today just to show the stunning diversity of color and pattern to be found in the mineral kingdom.

Complex Stories

Banded Agate/Jasper, Olympic Peninsula

When I studied geology at the University of Washington, my favorite class was one called "Structure" in which we tried to piece together the sequence of events that have altered rocks and landscapes by reading the stories within them. If one continuous layer in a sedimentary rock is offset along a plane, for example, you could infer that a fault had shifted AFTER the deposition of the layers. (see the faulted jasper in my August 25 post). Sometimes, however, multiple events can overlap, creating a very confusing picture.

That's what's happening with this rock, which I found among beach cobbles on the Pacific Coast of the Olympic Peninsula. I'll call it an agate/jasper (or "jaspagate" as I've seen it written elsewhere) which is simply another name for a rock that has features of both: the transparency of agate and the opacity of jasper.  Whatever you want to call it, this small pebble seems to tell the story of fracture and fill: an existing red jasper was fractured, possibly several times, and injected with quartz solution - both clear and vivid red. How did this happen?  I have no idea, but whatever the story, its this complexity that helps create this handsome visual pattern, one with tantalizing hints of the paintings of Jackson Pollock.

Faux Feces

Pseudo-coprolites, Salmon Creek, WA

Coprolite is  fossilized dung. (Greek : copros = dung, lithos = stone) It is a rare, but oddly compelling, fossil, especially if it can be shown to be from an exotic source, e.g. dinosaurs.

For many years, collectors have been finding what looked like coprolites in abundance along Salmon Creek in southwest Washington State.  I was there recently, and easily found dozens of these things.

However, most paleontologists say these are not coprolites at all, despite their similar morphology, but some sort of unexplained mineral deposit. Coprolites, it turns out, contain fossilized remains of plants (or bones and hair for the carnivores), or whatever the diet of the animal which left it.

These "psuedo-coprolites," by contrast, show no such structure, and their chemical signature is all wrong.

Too bad.  I think my grandson would love to have a piece of real dinosaur dung...!

Back to Mt. Rainier

Sunset and clouds on Mt. Rainier

 It takes about 3 hours to get from my house to Paradise, on the 5000 foot level of Mt. Rainier.  I dashed down there yesterday hoping to get some shots of wildflowers, which so far are about 6 weeks behind their normal bloom schedule. Well, after hiking up to my favorite meadow, I found the flowers just emerging from under the snow. If they bloom at all this year, it will be a miracle.

Driving home, I made a short detour to have a look at the Greenwater River just northeast of the volcano. There are few gem quality rocks on the mountain itself: too young and too active. But the volcano we see today rose through much older volcanics, many of which produce large quantities of agate and jasper. There are a couple of well-known areas for agate in the hills above the Greenwater, but today I decided to just poke around the riverbed to see what was washing down from the surrounding watershed.

In an hour or so I had a bag full of small agates, some jasper and even a nice piece of petrified wood.  But the find of the day was this good-sized multi-colored agate which I pried out of the riverbed. I haven't decided what to do with it yet - it seems criminal to whack it with my sledgehammer and run the risk of it shattering, so I may wait and cut it open - or polish the whole thing with the hope that it will reveal some nice patterns.

Agate from Greenwater River