What is and What Isn't (Part 1)
(It's a beautiful spot.)
On a recent wet placer prospecting foray to the Tusas Mineralized Region here in Northern New Mexico I came across an interesting and intriguing aspect of paystreaks that I thought I'd pass along to you. Like I always say, Ma Nature can do some pretty strange things with gold. But the paystreak thing is only a superficial lesson I want to pass on to you, as you'll soon see.
Along with Ernie Martinez, my mining pard, I headed back to a location we've been sampling and playing around with off and on since August of 2015. The Tusas Region is highly mineralized and back in the old days a decent amount of placer gold was taken out of some of its streams. The spot we've been working, however, doesn't contain tons of gold but the yellow metal is there just the same. The majority of it is quite small in size ranging from microdots to small flakes and, to a lesser extent, medium-sized flakes. Oh, and one small nugget thus far. Normally this isn't the sort of gold ground I'd spend a lot of time on, but I'm schooling Ernie up on the basics and the location itself is a gem in terms of natural beauty. In fact the natural beauty of the location is as big a draw as the small amounts of gold that lay hidden there. That's the one-two punch for all of us isn't it? A beautiful spot that has recoverable gold in it.
Bedrock is King
One nice thing about this particular location is the availability of shallow bedrock, much of it left high and dry above the current stream course. In case some of you newbies or greenhorns out there don't quite understand the significance of bedrock in your prospecting and mining activities, just be aware of the fact that true bedrock (or false bedrocks like clay layers) presents an impermeable barrier to the downward passage of placer gold and other "heavies" such as lead, oxidized iron, and black sands. In most instances, bedrock holds your best bet for finding concentrated gold. That's it in a nutshell. So bedrock is a good thing and something you should endeavor to reach and check, especially in wet placer areas. It's also your "go to" point in dry placer locations as well, but desert gold tends to be deposited a bit more erratically in general and reaching bedrock doesn't always mean you'll find gold there. But in wet placers? Bedrock is king.
(Bedrock, bedrock, and more bedrock.)
The overburden covering the bedrock at this spot ranges from a few inches to a few feet and, of course, is much deeper the farther you move away from the existing stream flow. That's workable bedrock folks. I'm not going to try and shovel five or 10 or 15 feet of overburden off of bedrock on a single day's excursion but I will work like a madman to clear a few feet off it. But 10 or 15 feet? Truthfully, I'm probably not going to do that in any context. I'm a hard worker when I'm out in the field but I sure as hell ain't gonna work that hard for the pitifully small amounts of gold at this location in the Tusas. We all have our limits, you see?
A Tip From an Old Timer
Well one things leads to another and Ernie wandered off downstream to do a bit of sampling. I sat and visually psyched out the usual spot we work; thinking, thinking, thinking. I'll do this each and every time I hit a location (wet or dry). Just sit there for a bit and check my surroundings, searching for possibilities and trying to get a line on where I think Ma Nature is dumping the gold. I strongly recommend you get into this habit as well instead of plunging into things with no idea of where the gold might be and then digging random holes like some crazed mole. Use your knowledge and experience while doing this, as well as your intuition or "gut" feeling. Then get to work. That's a tip from an old timer who learned the ropes from three exceptional old timers back in the day. Check things out visually first, analyze what you're seeing, and then start your sampling.
(Ernie doing his thing.)
A Light Bulb
As I sat there pondering, my eyes focused again on a section of bedrock we'd taken some decent (for this spot anyway) gold from in the past. We'd stopped hitting it because it had appeared to me that the small amount of gold that section of bedrock contained had "pinched out." Ernie and I had hit a small pocket or short paystreak there last year but then the yellow metal disappeared and after too many sterile sample pans filled with lots of heavy black sands but no gold, we gave up the ghost and gave that spot a rest. It was this very same spot I was staring at now. The first thought that came to mind was this. "We got some gold here before...therefore there's gotta be more." Not an Einstein-ian equation but a light bulb at least. So I started clearing off the overburden a bit higher up (upstream, that is) on this section of bedrock and taking test pans. The overburden gravels were sterile. No surprise there. Usually I'll toss them aside but it doesn't hurt to check them occasionally for color. But once I got down about eight inches or so I began pulling a few medium-sized flakes, sometimes as many as a half dozen per pan. Hmmmm. I was working a bedrock "box" of sorts where a deep depression in the bedrock ran parallel to the stream flow (not good) and ended up hitting a section of the same bedrock that ran perpendicular to the stream flow. Voila! That's the ticket.
(Getting down to the "box.")
I stopped what I was doing and walked downstream about 50 yards to where Ernie was feverishly panning. "Getting much?" I asked. "Nada" he replied, "Nothing." So in the most direct way possible I suggested he quit playing around and get his ass back to the old spot I was now sampling yet again. "Ya want to find gold? Then go to the spots you found it before." As I said this to Ernie I realized I was telling myself the same thing. Yes, I know. It's Gold Prospecting and Mining 101, "Go where the gold is." But sometimes we all have to be reminded of the basics and what is, what isn't, and what could be.
There's more to come so stay tuned...
(c) Jim Rocha 2016
Questions? E-mail me at firstname.lastname@example.org