Winter Beaches

Banded Jasper or...?

The beach below my house is primarily sand, esp. during the quiet months of summer, when the surf is at a minimum. But in winter, storming winds and tides throw rocks up onto the beaches, and right now there is a thick layer of pebbles at the tideline. This is perfect for sampling the extraordinary diversity of rocks that characterizes this ancient glacial landscape.

This good-sized cobble attracted my attention today. It was heavy and glass-smooth,  typically a sign of a hard rock like agate or jasper, but with some lovely green and brown banding.  I haven't seen anything like it here before - but that is almost always the case here : rocks deposited on my beach are likely remnants of boulders dropped by glaciers here 10, 000 years ago.

In any case, I popped it into the tumbler - and in a week or so, I'll be able to get a clear look at it. Then it will either go into polishing - or get tossed back onto the beach.

Alki Beach,  New Year's Eve Eve, 2013

Peacock Rock

Peacock Rock, Puget Sound

The water along the shores of Puget Sound was almost dead calm today, and the sun was shining: both relatively rare events here in Seattle.  It seemed a perfect day to prowl the shoreline looking for rocks, esp. where the rising tide washed over the beach, revealing the stones' true colors and patterns.

Along the shore of Lincoln Park is a favorite spot since the strong currents make for good-sized rocks, mostly free of barnacles and other marine life (I prefer to avoid killing things that live on the rocks, and for that reason avoid low tides).

I walked for half a mile along the beach, and my best find was this multi-colored, thinly layered cobble. I brought it home and cut through it.  It has a handsome patterning and wonderful, subtle colors. I haven't tested it for hardness yet, but I'm hoping its hard enough to take a polish. Either way, it's not like anything I've ever seen here before.

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.

I'm Back...with a Mystery

Mysterious Rock, Puget Sound

I have not posted for quite sometime, not having had much time - or weather - for rockhounding. But every chance I get to walk on the beaches below my house, I typically find something. In this case, a few weeks ago, I spotted this interesting cobble (about 2" long) and threw it in the tumbler. The polish revealed a fascinating pattern which I can't identify or explain.  Any ideas? A kind of agate?

(Click on photo to see a little bigger)

Surprises

By now, you will realize that my idea of heaven is to wander along local beaches picking up interesting stones and trying to piece together the stories behind them. I often fill a bag within an hour or so, and only weeks, if not months, later get to polishing them. So I can maybe be forgiven for not exactly remembering where I found this one, which emerged from the tumbler today. It is of a free-form yellow jasper together with what looks like a pinkish agate. Pink agate?  Never heard of it before - and as always, I have no idea where this rock originated, thousands of years before it landed on the beach where I found it. Yes, it would be nice to know: I'm guessing there are more like it...

Under the Sand

Sometimes a rock will catch my eye with only a tiny spot visible - that was the case with this handsome stone that was mostly buried under the sand. No idea what it is, with its smooth swirls of red and green, but it was definitely worth digging up and tossing in the bag.  It'll be a month or more before the thing gets a polish.

Using the "Search Image"

Petrified Wood, Alki Point

When I patrol the beaches near my home, looking for colorful or unusual rocks, I try to keep a mental image of what I am looking for, what scientists call a "search image." This refers to having a visual sense of what you're after when you set out, which can give you an advantage in spotting one specific kind of rock among thousands. Normally, I look for bold patterns, or bright colors - the easiest things to see. But today I made an effort to look at black rocks. My goal? To find specimens of petrified wood.

As I have mentioned in earlier posts, there is a form of black petrified wood that I have found many times on local beaches, though normally as small cobbles that reveal their patterns only after polished. I have no idea where the rock originates, but I am guessing it is somewhere relatively nearby, simply judging by the relative abundance of the stuff.

So I set out today with the idea of concentrating on finding these pieces of dark wood. This may be why I found this piece within 15 minutes of searching the beach, by far the largest piece of petrified wood I have ever found along the shore.  Did my "search image" make the difference, making this rather drab piece of rock stand out?  I think it did.

Though this piece looks drab now in its unpolished state, I will try and post a picture of it after polishing - look for it a few weeks from now. Until then, I will probably be back looking for other pieces of streaky black rock...