Monday, November 9, 2009

Rockhounding Adventures of the 4th Kind: Digging Halite

Yes, this is that rich a color when it's in your hand!

I've been a rockhound since I could walk, but my adult "career" began 30 years ago. It's been a long, strange trip.
However, over the decades of digging, collecting and working with rocks & stones, no experience has been so strange, so compelling, so STINKY as "digging" at Searles Lake.

Located in the "heart" of downtown Trona, California just a little over 30 minutes drive from Ridgecrest on Hwy 178, Searles Lake is the home of Searles Valley Minerals, a world leader in the production of industrial saline & borate chemicals.
Trona is a fairly typical, quiet desert town 51 weekends out of the year. But on the 52nd, watch out!

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Every year, the second weekend of October sees rockhounds, mineral enthusiasts, the geologically conscious and just plain "seekers of the unusual" invade this remote outpost of miners dreams for the Searles Valley Gem & Mineral Society "Gem-o-Rama." They come from EVERYWHERE in search of minerals pedestrian & rare. This panoply of humanity includes peoples of an amazing variety, all hosted at a truly great Club Show.
We've met Americans from many states, and folks from as far away as Japan & Germany at Searles Lake. I've had the strange experience of washing hanksite in stinging, stinking brine between a high school kid from South Central L.A. and a Japanese tourist, both grinning ear-to-ear, as small kids tried in vain to dig their own way between my legs to the brine trough.

In addition to the lovely aroma of Searles Lake, Trona is one of the gateways to Death Valley. The nearby destinations for rockhounds include Ballarat and the Darwin District, with the lonely peaks of the Panamint Range as an arid background.

The desert is a familiar friend and yet a formidable challenge when preparing for any collecting excursion. The extreme conditions of collecting at Searles Lake require tools & accessories that might seem strange to an idle onlooker.

One of our 2008 halite on nahcolite plates

Among the unexpected items are, for the "prissy" collector, elbow length rubber gloves. Yes, my friend, in the desert! But these will almost always be discarded, as you simply can't feel anything through the rubber, and they soon get teensy weensy little holes from the sharp edges of the nahcolite "matrix" that hosts most of the lovely halite crystals. And what's the point in wearing holey rubber gloves?

Yes, the brine will affect your hands, but Bubba, you're tougher than that, aren't you? In the afterglow of collecting that lovely halite, you'll sit staring at your bounty, and be glad for the God given gift of exfoliant soap!
Trust me, if you're one of those guys or gals who itch for "rock softener" (dynamite) when confronted with an agate seam, the several weeks of itching and peeling and inevitably, a few small cuts from those aforementioned sharp edges will be a fond reminder of the strangest 3.5 hours of collecting of your year.

One of our lovely 2009 halite specimens

The next item of apparel to be discussed brings up one key point: Never, ever wear clothes on Searles Lake that you aren't ready to "sacrifice." The "Goddess of the Salt" will claim any non-rubber item of clothing, turning a pair of jeans, once dried, into a standing sculpture. They'll literally "stand in the corner."
I recommend a sturdy but well worn pair of jeans, though I've found the least affected pants to be a pair of khaki's (Cherokee brand) from Target.
The shirt should allow you to apply copious amounts of SPF 50 on any exposed portion of your body, and a wide brimmed hat will keep your friends from calling you a "redneck" for several weeks.

One of my favorites from 2009

The most important item of clothing is footwear. It needs to be comfortable, yet disposable, unless rubberized.
Personally, I've a pair of rugged slip-on Oxfords from WalMart, the "no-skid" kind. I wear these only on Searles Lake. Next year, I hope to have a pair of "hip waders."
If your feet get wet, and they likely will, it's better to have a pair of permeable shoes, rather than a pair of insufficiently tall boots.

A lovely clear cubic halite on nahcolite from 2009

As noted before, the "dig" takes place on a saline lake bed. Now, this isn't your average Mojave desert playa ... Naaaaaahhhhh, that's wayyyyyyy too easy. No, this is a real "got water" type of lake. And, where there's water, there's almost always life ... of some kind.

The kind of life in this lake is pretty much singular, unless you call a "salt duck" life. What, you ask, is a salt duck? Well, to put it simply, when waterfowl land on this lake, they quickly become saturated with the heavy saline brine, preventing any future takeoff. They're soon, quite literally, mummified.

The "top" is lovely, but ...

The bottom is lush!

Now that you've experienced a "King Tut" moment, let's get on to the real wildlife of the lake,
which is also the agent that imparts vivid colors to the halite and others minerals.
This is a type of bacteria, in different shades of red & green, classified as halophyllic. This term quite literally means "salt loving." The red colors are much more common in halite than the green, which more often imparts it's color to hanksite.

This unusual "rope" specimen ended up as a part of a Harvard Museum of Natural History "hands-on" learning exhibit ...

This one, too!

Aside from its vivid colors, the most notable characteristic of the bacteria is the incredible STENCH it generates. This is caused by one of the byproducts of the digestive cycle of that lovely bacteria.
Just as we generate methane, scented by compounds called ketones & terpenes, these bacteria generate a deadly (in larger concentration) gas called hydrogen sulfide. It smells like rotten eggs, or as I like to say, "Satan's Undershorts."

Now, some say this would be a deal breaker, but just like a dairy rancher, you quickly get used to even this pungent aroma. Heck, some people (including a small 6 year old girl of my acquaintance) even claim to enjoy the smell!
Truth be told, I guess I'd have to count myself among them.

This one has such varied colors, with clear cubic crystals throughout

The next item to be attentive of is tools. Never take anything you aren't willing to "sacrifice." I've lost a favorite masonry hammer, and found hammer and screwdrivers. Paint every handle a bright color, "emergency orange" is best.
Be aware, if you don't clean every tool you use quite thoroughly, the salt will literally eat it. (I'll post some pics of my "less than loved" tools.)
I generally hit the Hardware Store and pick up a short handled shovel ("pack shovel"), garden tool set with 3-tined weeder & trowel, and pry bar. I also take a pick/mattock & long handled shovel, my most used tool. Screwdrivers and wooden tools that won't mar the specimens are good. I always bring a couple of pairs of bamboo chopsticks, too.

Now to the fun ... DIGGING! And yes, it is to be considered digging. I'll tell you all (well, most) of my digging secrets.

There are lots of different ways of finding halite on Searles Lake. All of them include getting wet with brine and quite smelly.
The best way to come home with halite is to dig. Now, I know it seems silly to say that, but it's somewhat daunting, at first. You're surrounded by acres of crusted white salt, with heaved up cracks, and the crust is crunchy & feels unstable.
Be of good cheer! No matter how hard you might try, even if you break through completely, you can't sink. It's a saline brine, so you will float if you land "in the drink."

I prize all of the various forms of halite from Searles Lake, and they're all found in different ways. Some can be found by prying into "cracks," then turning over the loosened surface crust.
This yields the strange "skeletal" and hoppered halite crystals, in snowy white to "angel" pink colors. But these are only the first of the many forms.

Under the stark white surface, you may find a pond. I usually walk about awhile, testing the surface, and looking for "ponds." These ponds are my favorite halite collecting holes, and yield the bulk of my favorite specimens. Some years, our best halite will be found in the covered ponds. This was the case in 2008. In 2009, it was a totally different story.

Another classic 2008 plate

In 2008, the prevalent form of halite that we collected was in fairly flat "plates" of pink to ruby red cubic crystals, on wafer thin khaki to green nahcolite. These were found mainly in ponds we broke open through the surface.
This year we found many more 3-dimensional halite on nahcolite (baking soda) matrix. The nahcolite forms in botryoidal to vermiform massive form. even in the wafer thin plates, it's TOUGH! I have yet to break even the thinnest plate, and if you chose to try and chisel the thicker formations, GOOD LUCK! Hammers and chisels simply bounce off the rubber-like material.

Your best bet, if you must try to break the nahcolite, is to crack it with a pry bar or gad point.
But, that takes time, time you don't have.

So, what works the best? Get into the pond, and feel about in the brine. Brush the formations with your hands, lightly at first. Feel the shapes, and look for "ledges."
When you find a ledge, try and feel under it. Most of the time, any cracks and voids will be loosely filled with granular halite & nahcolite, with the occasional halite "floater" crystal. Brush and dig away at that material with your fingers, wooden "chop sticks" and garden tools.
As you dig away the material, test the newly exposed formations to see if they wiggle. Any movement may signal a "plate," or crystal cluster on matrix.
When you find one, work it loose with one of your garden tools, shovels or small pry bars, but always be careful to avoid scratching the surface or moving the tool beyond the outer edge of the piece. This will help to avoid scarring or breakage.

If you're lucky and "hit the jackpot," you'll find the "perfect pond." For me, this is like the one that yielded so many little "hillock" specimens. These are, as they sound, hand-sized hills of nahcolite covered with "gardens" of multi-colored crystals. These are generally cubic in form, ranging from micro-crystals to over 9mm, but will vary widely in form.

This years perfect pond was literally filled with over 100 separate specimens, which had formed in the brine as a loose formation. After finding this with my hands, I took my long handled shovel and gingerly searched for "pry points." When I found one, I slipped the tip of the shovel carefully into it and levered upwards to loosen the formation. When loosened, I'd slide the shovel under the freed pieces, then slowly lift them out of the brine. We were able to collect many flats by this method

That "peach" pink specimen

The most unusual crystals I found this year were peach colored, "hoppered" to cubic on a tan botryoidal nahcolite matrix. This small cabinet sized specimen is currently available on our eBay Store.

Be sure to take a look at our store, and don't hesitate to contact me if you're looking for a really special halite specimen. I have some stunning multi-pound decorator specimens that will be posted for sale soon!

In conclusion, if you're looking for the ultimate collecting story, it's hard to beat Searles Lake!