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Anatomy and Location of a Gold Nugget Patch

It’s day 43…or 51 or maybe its only day 29 in the rolling red-gray expanse of the Mojave Desert. I can’t remember anymore and I was never keeping track anyways. My metal detector coil is swinging in front of me like a clock pendulum, undamped and infite, and I’ve fallen into a walking hypnosis broken now only by the sudden and painful report of a cholla cactus ball embedding itself into my thigh. I retrieve a comb from my pocket and exorcise the demon weed from my leg with one quick swiping motion (which is the only good way to remove cholla) and the blood dripping down my leg feels remarkably cool in the oppressive heat.

cholla cactus

Cholla – The name of my pain.

It’s been a week since my last gold but the high from finding it keeps me moving forward. Every faint warble in my detector threshold causes a brief yet short lived rush of excitement as I turn over yet another hot rock hoping the signal indicates something more than just excess mineralization. Magnetite, limonite patches, hot basalt, hellish burnt black minerals of mysterious classification. None of it worth a kick in the sand, but I spitefully pound my composite toed boots into a few chunks anyways – if only to clear them out for the next unlucky prospector to hunt this wash. I feel the cholla blood crusting on my leg and I miss the cooling streak so I decide to pause and avail myself of a tiny slice of a shade behind a gangly old creosote bush. I empty my pockets out and gaze upon what is a normal faire of junk targets: a depression era Levi’s rivet, a few jacketed .38’s, odd bits of wire and rusty tin, 5 drywasher fabric nails, and an old-timer’s 44-40 slug – probably missed his javelina and went hungry. Most days my pockets are filled only with junk like this, but a week agothat same pocket was weighing heavy with the yella’ when I had the luck to stumble upon a nice patch. the story of which I’d like to share with you.

Patches to the greenhorn gold prospector can often seem like a mythical contrivance. Newbies often go months, a year, or more before finding their first nuggets metal detecting. And it’s frustrating when it seems like every old timer has a story of some old patch he found that just keeps producing nuggets to this day but of course no one wants to tell you where they are or how to find them. While I’m not one to dispense exact locations, I will tell you exactly how I found my latest patch (and how you can do the same), and describe for those who wonder what one looks like what I actually found therein.

For those who like to keep track: I’m using a Minelab GPX 4500 model metal detector. Costs as much as a good used 4×4 truck and I’m still waiting for Australia to grant me an honorary citizenship for my personal contribution to their economic advancement. I’m swinging a 14×7 mono coil being held together by Gorilla tape and dried mud, but it’s put me over some of the best nugget patches I’ve ever found.

I can see my patch from where I sit behind this my creosote shade. To the east is a long ridge running north/south and a faint white streak from a decomposing quartz stringer is showing cutting across the ridge. There are actually 3 stringers, the other 2 not visible from my vantage, and this is important because they led me to locating the patch. But I didn’t find this place on the ground, I found it while sipping coffee in the comfort of my camper. On aerial imagery, for those who are familiar with it, the quartz often shows up as faint lighter-colored streaks cutting through the more grayish common alluvium and darker gray host rock.

Let’s take a step back for a moment. Research is the most effective tool for finding new gold bearing locations, so I wanted to narrow down my search area first rather than spend endless hours scrolling across ambiguous aerial photography. In this particular case I had determined after researching the mining history and geology of this area that certain Proterozoic age granites had hosted gold bearing quartz veins that were discovered by prospectors long ago.

Gold Nugget Patch Map

A map depicting gold nugget locations, quartz outcrops, and surficial geology. Click photo to enlarge.

I also knew from prior experience that I tend to make nice discoveries around faulted zones. So my first task was to overlay a geologic map across my aerial photos and determine where the physical rock structures I was interested in were located. On top of it all I overlaid a map of all known gold producing mines in the district so I could determine if their mines were struck within my target host rock and also to view the character of the mineralized zones in which they had driven their adits so I could find similar areas.

Using the known mine location area as a starting point I located a fault line between the Proterozoic granitic rock and an adjacent (gold barren) metamorphic formation and scanned on the aerial imagery an area of about 1/2 mile to either side of the fault from it’s beginning to end. Using the mine locations as a reference I could see that the strike of the larger veins tended to be around 30 degrees  N/S of the fault strike so as I was scanning the fault district I kept a close eye on any lighter color abnormalities in the imagery which could be unexplored quartz dykes.

Bingo! I found a prospective location with what looked like 2 possible large quartz occurences (and later found a 3rd on the ground). Even better was the fact that alluvium covering bedrock in the drainages was Quaternary which was formed during an age that for whatever erosional reasons tends to host most gold than the much more expansive Pleistocene-age alluvium in this particular area. And the closest 2-track road was at least 3/4 miles distant so I had hope that I would be one of the first to detect this locale. (note: the accompanying map is NOT the actual location for obvious reasons as I’m still hunting this patch but I looked long and hard for a similar location that would properly represent the actual for illustrative purposes)

After a usual restless night of sleep, hands grasping helplessly in the air in want of a 2 lb gold slug as I toss and turned thinking of my inevitable fortune and subsequent luxurious life, I awoke and promptly journeyed to my new found detecting spot. A short hike in brought me up a large gulch after dodging cactii and buzztail like my dog dodges the bathtub, and I arrived at a short feeder wash I had marked off on my GPS the night before. I could see the two quartz stringers I had spied in the aerial imagery disintegrating out a large ridge in front of me (which I currently stare at from behind my shady creosote as I write this on my tablet) and the ground showed many scattered pieces of rusty, vuggy quartz scattered about.

I turned my detector on and began a slow and methodical scan up the gut of the wash, making sure to check the eroded sides and bench tops as I moved. I noticed a few somewhat fresh detector dig holes and my hopes began to sink as I also saw the unmistakable imprint of a Bates non-metallic boot in the sand.

gold nugget

The first nugget in my new patch rears it’s head.

But no sooner than my when my groans had ceased echoing in the nearby canyon I received a faint but sweet sounding mellow signal in my headphones…right in the gut of a boot swept fresh hole.  A flat black nasty looking rock lay at the bottom of the hole and I assumed I had found a hot rock the previous detectorist had conveniently uncovered for me, but I jabbed my pick under it and ripped it from it’s home and swung my coil once again. Still there! I smacked my pick into the hole a few times to loosen up the dirt and subsequently discovered the target was now out of the hole. A brief moment later I had a nice 0.13 gram nugget gleaming in my grimy paws! Had the first person to hear this target spent another 10 seconds investigating the hole this nugget would now be in their pockets. And even better as I moved further up the wash and onto the benches I noticed that the previous occupant had apparently abandoned this spot as there were no long any footprints or signs of fresh digs.

As I continued scanning randomly I found another little 1/4 grammer, then a half grammer… Every 30 minutes or so I found a new nugget, a few in the bottoms of small feeder washes but the majority resting on the benches right near the wash edges. I realized I had found a new patch after the first 3 nuggets so I adopted a gridding approach to ensure that I covered all ground equally and ended the day with 7 nuggets, exhausted  As I slogged back to my truck I couldn’t help but wonder what lay over the high ridge and within the wash it hid on the other side.

After arriving back at camp I plotted all my finds and compared it to the map which I had created to find this patch. One thing seemed clear: the nuggets had to be eroding from the quartz I had spotted as they were almost all found within in a topological gradient that led right back to those quartz source rocks. Observing from my map that the quartz also outcropped into the wash on the other side of the large ridge my target location for the next day became clear.

Another night of restless sleep followed by 2 spoonfuls of Folger’s crystals and a half cup of water in the morning, my poor man’s espresso brought me on bounding legs to my unexplored wash as the sun began it’s relentless eternal circumnavigation of the sky. Arriving at my patch I flicked on my detector, gave it a quick ground balance, and I began walking up the large ridge towards the quartz outcroppings. Someone had given the quartz a pounding with a hammer or pick, probably an old-timer as I noticed a tell-tale Prince Albert can rusting lonesomely on the ground. I rushed over the apex of the ridge and noticed that there was a fainter 3rd quartz stringer I hadn’t seen on the aerial imagery cutting right across the center of the large wash before me and my spirits rose as I wondered if this too would produce for me.

My hopes were not in vain as I got a slamming signal within 10 minutes of poking around in the bottom of the wash.  I have a video posted at the end of the article and you can see what I pulled out of the ground. In a small 15’x15′ area I dug up a 1/3rd oz’er, a 5 grammer, and another half grammer. I hunted the entire wash thoroughly (or so I thought) and found nothing else for the day but I know from experience a patch is never truly cleaned out. I’ve since revisted the patch a few times and I’ve managed a few more scattered pieces and you can see the grand total thus far in the attached photo.

gold nuggets

The total take from nugget patch, all together over 2/3rds of an ounce.

One thing is clear, I never would have randomly found this spot without research. An hour on the computer led me to a spot that at least one other detectorist had found probably by chance but he had passed up probably because he didn’t know that there was a “magic” combination of geologic factors combining here to create what I’ve found by experience to be “honey holes”. Had he also dug that first nugget I found in his old dig hole he may well have cleaned out my patch and left me wondering why this optimal looking location was in fact barren.

In that way, there is always a certain element of luck involved in gold prospecting, but our job as modern prospectors is to eliminate as much of the “luck factor” as we can and I hope this example has shown how a person can go about doing this using computers. It also doesn’t hurt to have the experience to know what sort of subtle signs and indicators to look for and that my friends can only be acquired by setting boot to dirt. So, on that note I will see ya in the hills!



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