"Sniffing" Out Junk Metal to Get the Gold (Part 2)
(You couldn't ask for a more beautiful location to prospect.)
Some very good and highly informative comments were sent in regarding my earlier post in this series and I think some of you readers out there might want to take a look at them, especially if you're not well-versed in using a gold detector to "sniff" out potential placer gold deposition points. In this post I have a bit more to say in this regard and I have also included numerous photos of the location where my pard Ernie Martinez and I have been prospecting.
First off, my choice for prospecting this location was four fold: 1) I'd been told by locals (non-miners) that gold existed here; 2) the location is situated in a highly mineralized zone (the Tusas Mineralized Region); 3) being the hard-headed old timer that I am, I wanted to prove to myself whether color existed here and in what size and quantity; and 4) it provides a good learning experience for Ernie who I'm "schooling up" on the basics (he's proving to be an apt pupil and one hell of a crevicer!). After a half dozen trips to this location, I proved what I set out to. There is gold here, although it's very small in size, quite spotty, and tends to gather in sparse "pockets" in sections of bedrock crevices. No two crevices are alike at this location and some contain placer gold while others don't. Bedrock abounds here and it's primarily rough, angular, and highly fractured which is exactly the sort of bedrock structure you want to look for out in the field. An interesting feature here is the prevalence of "V"-shaped bedrock trenches that are 10"-36" wide and that probably extend for many yards (this is a supposition on my part since overburden remains to be removed). The unfortunate aspect of some of these trenches is that they run parallel to the existing stream as opposed to perpendicular to it. If you're a newbie and don't understand the significance of this as it relates to gold deposition hit me up on e-mail and I'll explain, OK? Anyway, each trench Ernie and I have sampled has contained gold in greater or lesser amounts. The best test pan from a trench came from a mere handful of clay-bound material resting at the bottom of one of the "Vs". When panned, ten-to-twelve pieces of gold showed up ranging in size from medium-sized flakes on down to flour gold. The gold itself is very pretty...bright yellow in color and probably running in the high .800s to low .900s in overall purity. This is an eyeball "guesstimate" based on my own knowledge and experience in the field.
(Close up of gravel-packed section of bedrock at this location.)
(Although some distance from our current location, large tailings "stack piles" show evidence that good gold was recovered in this area in the past.)
A Reliable Tool
Over the course of my 35-year small-scale mining and prospecting career I've come to know just how important bedrock is to finding and recovering gold, but more importantly, how significant identifying likely deposition points on that bedrock can be. Knowledge, experience, and a practiced eye helps a great deal in this regard, but a good gold detector can be a valuable asset in "sniffing" out likely spots to dig and sample. The presence of oxidized iron or lead in any form packed into bedrock crevices, depressions, or trenches is a revealing clue to the possible presence of gold since that sort of junk metal has a specific gravity close enough to placer gold to end up in many of the same spots the gold itself has come to rest in. Granted, gold's specific gravity is higher than these junk metals, but their overall weight and density is close enough for them to end up resting on or anywhere above bedrock. Remember, bedrock forms an impervious layer that prevents any further downward movement of gold and that's the heart of the matter at this particular location. There is exposed or partially exposed bedrock nearly everywhere one looks so it's a small-scale miner's dream...well, it would be if there was much more gold available and it had some real size to it. As I stated previously, my Gold Bug Pro has proven itself to be a very reliable tool for determining which crevices or trenches to sample based on its detection of junk metals (oxidized iron and lead) and black sand deposits. I simply fire it up, adjust the settings, and start scanning the bedrock in All-Metal Mode. Once the machine detects a ferrous bedrock crevice or trench target that spot is dug out and sampled. I've said in the past that when you're crevicing or sniping you should clean those cracks or crevices out until they shine. This is especially true at the location we've been prospecting since some of the best sample pans have come from bedrock crevices or trenches that we've literally "brushed" clean. It's a must at this spot since the gold is typically very small in size.
(Yours truly using the Gold Bug Pro to scan a partially cleaned "V"-shaped bedrock trench.)
(This location's gold is mostly small, sparse, and spotty.)
Can't Get No Satisfaction?
Since Ernie Martinez is a relative greenhorn when it comes to all things gold mining, I've taken him under my wing and have been mentoring him at this location. Ernie makes a great pard and student, and I take great joy in showing him the ropes and seeing how much he enjoys what he's doing. He's a quick learner and will undoubtedly make a great small-scale miner down the road when he's gotten more experience under his belt. Ernie definitely has color running through his veins, that's for sure! This said, I have to admit that I don't share the same measure of excitement he does in finding sparse pans of bedrock color. I guess I've been around the mining block too long and, truth be told, I'm a bit jaded. As you experienced miners and old timers out there already know, once you've run small-scale equipment in a variety of conditions and environments and have recovered some REALLY GOOD gold in "richer" locations, it's hard to get all pumped up about a spot like the one Ernie and I have been prospecting that's really not suitable (i.e., there just isn't enough gold!) for setting up and running mining gear. All this said, the point I'm not making very well is that I proved what I set out to prove and, moreover, I've instilled the love of prospecting and small-scale mining in the heart, soul, and mind of another person. That's where my satisfaction lies these days.
(Ernie M. hard at work.)
Gold can be found in very many ways, don't ya know?
(c) Jim Rocha (J.R.) 2015
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