What you Really Need to Know About Tertiary Channels (Part 6)
(Hydraulicking for Tertiary gold was very effective but pretty much ruinous in environmental terms.)
Two Main Approaches
We've talked about some of the difficulties in working Tertiary Channels, especially as these issues relate to small-scale miners. What are the best methods for working these sometimes unbelievably rich gold-bearing gravels? Read on, my friend.
There are two main approaches used in working Tertiaries, both historically and today. The first is hydraulic mining...a method you won't be able to employ without bringing fire and brimstone (not to mention lots of lawyers) down upon your head as you incite the wrath of every two-bit, whack job "green weenie" here in the West.
Gold Prospecting Books
Anyway, in my limited understanding of our complicated mining laws, hydraulicking has been illegal in the U.S for quite a while. In truth, that's probably a good thing and this is just about the only time you'll ever hear me agree with environmentalists (radical or run-of-the-mill) in general. (See? We don't have to join the other side even if we do agree with them once in a million years.)
What's hydraulicking? In the strictest sense it's simply the use of high-pressure streams of water to erode, tear at, dig out, and collapse gold-bearing gravels, including Tertiaries. If you want an example of how hydraulicking works try the following mini-experiment:
1) Step into your yard and grab the nearest garden hose and nozzle.
2) Turn the water on as high as it'll go.
3) Set the nozzle in a manner that focuses the most intense, high-pressure stream possible.
4) Point that sucker straight at the earth surrounding your wife's new garden and let 'er rip.
5) Watch closely as the earth erupts, flowers tumble over, and a silty sodden stream of waste begins to pollute the surrounding terrain.
6) Jump in your car or truck and beat feet for safer ground...maybe you'll be able to return home in a day or two when your wife (or hub) has cooled down a bit.
You may be smiling but the fact of the matter is that, although imminently effective, hydraulicking was absolutely devastating to the surrounding terrain.
During the California Gold Rush hydraulicking was employed to great effect, especially against Tertiary gravels locked higher up within the surrounding hillsides at locations like the Malakoff Diggings (and elsewhere along the Yuba River drainage). Entire streams and rivers were diverted and mile after mile of wooden water flumes were constructed to feed these insatiable hydraulic "beasts."
Using canvas hose and huge, cast-iron nozzles called "monitors," miners of the day were able to tear down entire hillsides (trees, boulders, and all) to reach Tertiary gravels and bring them down to ground level, where they funneled them as a viscous slurry through a series of connected sluices boxes called "long toms."
After all that Tertiary gravel had been run through their "long toms," California miners plucked the larger nuggets out of their sluice boxes and then used mercury to amalgamate their gold-rich concentrates. The amalgam, consisting of fine gold, flakes, and smaller coarse pieces of Tertiary gold was then processed and the gold recovered and converted into bullion.
These hydraulic mining operations were typically massive endeavors formed by mining companies or "associations" that employed dozens and sometimes hundreds of workers who were paid an hourly wage or, if luckier, a percentage of the Tertiary gold take. Because of the equipment and manpower needed, hydraulic mining operations were never small scale nor were they well suited for small-scale mining approaches.
"Forget About It"
Eventually, the farmers and ranchers downstream of hydraulic mining operations got tired of having little, if any, clean water and having their fields and pastures turned into quagmires of waste slurry. They convinced those in power and authority to ban hydraulicking in California and thus it remains so to this day. (Hell, the fact of the matter is you can't even use a suction dredge in the once-Golden State these days.)
Sure, you can still use this method to access and process gold-bearing gravels (including Tertiaries) in some 3rd World countries and in parts of Central and South America and Asia. But if you're a small-scale gold miner here in the United States all I can say is "forget about it."
I'll talk about the other main mining approach for working Tertiaries in my final post on this topic. Until then, be safe and keep smiling.
If you liked this post, you may want to read: "Good Spots for Gold in California's Motherlode: El Dorado County"
(c) Jim Rocha (J.R.) 2012
Questions? E-mail me at firstname.lastname@example.org