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Black Bedrock Gold

This past season, I had the opportunity to work what I can only describe as an old placer cut. It wasn’t anywhere near the size of a regular placer pit, and the cut itself was only about fifteen feet deep, but however they’d figured it, they’d hit bedrock at that depth, yet the other excavations in the area had to go much deeper, 30-45 feet, to find that black bedrock.

I’d walked and driven past that cut numerous times on my way to a couple of larger workings upriver. So, one day when the clouds were keeping the summer day cooler, I decided to drop into the cut and have a sniff around with the GPX 5000 and the Gold Bug Pro.

In reference to the two detectors, and as I’ve been asked about this before, I’ll explain why I pack two very different machines when I’m nugget shooting. I don’t think anyone would argue that the GPX 5000 is a fantastic gold machine, and I have a tiny coil for it that’s a true sniper on small stuff, so why get outfitted with two different detectors when one will do the job? Well, the Bug Pro is a VLF machine, so it’s ability to ID iron is a real asset (vs. a pulse machine like the Minelab GPX which has quite limited ability to deal with iron vs. a top-of-the-line VLF, and as well, the Minelab has no meter system to give visual feedback). As I do a lot of detecting where big equipment has shed all kinds of metallic slivers and chunks, the iron ID muscle of the Bug Pro is a huge plus. That ability to ID certainly comes in handy in spots like I was detecting that day, and in severe cases where there are heavy concentrations of bits of steel on the bedrock, I can sometimes find gold (if I know there’s a good chance that it’s shallow) by using the onboard discrimination circuitry of the Gold Bug. (The little Minelab X-Terra 705 is great for this as well, and has done the same job.) In reference to discrimination mode, I believe everyone knows that depth is lost by using it in gold-bearing locations, but sometimes if there’s overwhelming trash, a loss of depth is secondary, especially when working bedrock. I mean, I know I can punch much deeper in all metal mode, but all metal means exactly that, and when bucket and track have continually worked a spot to grab dirt from the surface of the bedrock, the resulting signals can drive anyone crazy, especially me when I’m tired and getting cranky (It’s not just the bears that get cranky in the mountains!). Yes, a magnet helps clear an area, but if there’s clay present, which there always is where I’m currently working, the steel signals that are trapped and covered by it become a recipe for detecting insanity.

The day was pleasant. The damp, earthy smell of clay permeated the cut. A small seep was trickling water over the bedrock as it wound its way to a pool at the lowest part of the excavation. With the water wetting the bedrock in summer, a small squadron of tiny brown and orange butterflies were taking advantage of the free drinks. Every once in a while, a massive bluish-green dragon fly buzzed me getting a closer look at my face for some reason, its opalescent eyes and wings testament to Nature’s artistic genius; its flight capabilities testament to the insect’s unhindered mobility of flight or direction, an ability that significantly outperforms any of man’s weak attempts. The sky that day was partly cloudy with very little breeze, and the green timbered twin valleys I could see above the lip of the cut veed gently and beautifully into the main valley evidence of yet another marvel of Nature’s design genius.

The sides of the cut were littered with boulders of varying sizes. The bedrock itself sloped upward both directions from the pool, with the northern portion hosting a comb-like rise of friable rock, standing plates oriented perpendicularly to the bedrock base, sheets that varied from about a half inch to an inch and a half in width. There were pockets of clay either resting intact on the bedrock throughout the pit or ones whose motion was frozen in time when they’d oozed down the sides of the cut like tan, smooth, miniature glaciers.

I took the Bug Pro from the carrying bag and assembled it. It’s an nugget-shooting outfit that goes together in a hurry. It’s only time consuming feature, which is minimal, are the twin screws that attach the control box to the shaft handle. I turned the machine on and checked to ensure the batteries were good, then I started for the southern end of the cut. After I’d used the ground grab to balance, I started scrubbing the bedrock with the stock elliptical coil (I always buy coil covers for this reason).

The bedrock was quite smoothed off at that end of the cut, but I noticed there were pockets of clay deeper than the ones located at the pit’s center, or indeed at the northern end. I slowed down and scanned carefully. Not long after, I got a nice signal where a pocket of clay was trapped between two large plates of bedrock whose sides protruded just enough to stop the machines from getting it. By way of explanation, when a large placer operation is running, they are always concerned about volume; as well, they usually have excavators and dozers preparing a new cut, so time to chase small pockets is a luxury they don’t have, especially this far north where it’s always a race to get the gold before Old Man Winter ruins the party.

But, I’d better get back to my story. I took out my pick and scraped off about an inch of clay from the pocket’s surface, scanned it again, and the signal was much louder, but still displayed no ID on the signal meter.  I scraped off more clay, scanned again, and this time the meter jumped into the sweet spot and held steady. At this point I knew it was either gold or one of the few hot rocks clever enough to act like gold. I removed more of the clay, scanned again, but the signal was gone. It was in the pile resting on the bedrock. I scooped the pile and ran it over the coil—a nice yelp! It didn’t take long to sort the target out, and a sassy 2.2gram nugget was soon in my hand. I pulled out the little plastic bottle from my pocket and gave that nugget a new home.

Continuing on the same line I hit another pocket of clay, smaller than the first. This time the signal was very sharp, sweet, and it boosted the meter into the sweet zone right away, so I knew the target had to be close to the surface. I liked my chances. Out popped a round nugget that hit the scales at just under two grams.  It joined its brother in the bottle, and as I swirled the bottle those twins produced a nice golden growl. I kept at that end of the cut for a while; I even moved some of the boulders to see if anything was hiding under them, but I got blanked. So, I headed back the opposite way and came upon a little pool of water off to the side of the cut. There was a lot of clay in the area, so I took my time. Soon, I’d captured pewee; he weighed in at .6 of a gram, but he had a buddy too that had been on a workout program of some kind for he hit the scales at just over a gram.

I slowly kept working the bedrock until I hit the edges of the main pool. At this point I’d like to elaborate on another nice feature of the Gold Bug Pro; as the coils are waterproof, I slid the coil into the water. Moreover, because I had my mining boots on, I followed the coil to detect the bottom of that water. I was rewarded with two small pieces that totaled just under a gram. No matter where I went after that, there were no more signals, that is, until I swapped my Gold Bug Pro for the Minelab.

I went back over the bedrock with the GPX trying to see if I’d missed anything, and the Minelab did not disappoint. It sniffed out some deeper pieces that were down between plates that the Bug Pro didn’t have the punch to find. By the time I was done detecting, I had just over 8.5grams in the bottle, and what a growl those pieces made when I swirled the nuggets in the bottle by my ear. (In case you’re wondering why I spin the nuggets in the bottle, that tradition started many years ago way up north with my prospecting buddy that’s in his 80’s now. It was a thing we used to do and laugh about while we listened to the rumble of those nuggets in the bottle [our immediate area only has flour gold, nothing that would rumble or growl in a bottle in any way]. I love to keep that tradition alive.)

So, I crawled out of the cut, headed to my quad and pulled a couple of pans out of the rack, grabbed a shovel, then climbed back down. That comb of bedrock had me intrigued. Even though it hadn’t sounded off with any nuggets, the orientation of those plates made me wonder at how they couldn’t work as a gold trap for finer gold. Well, after prying those sheets apart, then scraping them off and washing any clay and sand into the pans from them, I panned out a couple of grams of fine gold. It took quite a while, but with the pool of water handy, it saved time hauling it to the river. The gold stopped however where the plates died as they splintered off the hard, solid bedrock underneath, for there were no more spaces between sheets to trap any gold. I’ve run into this lots of times when working friable rock. It’s weathered and loose where it’s been exposed or hammered by stream action, but then it turns solid and un-fractured as you go deeper. Regardless, it had been a while since I’d crawled out of a hole with about a quarter of an ounce of gold, and it felt right good, yet the summer only got better from there.

More to follow as I find the time, and all the best,

Lanny