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 Nuggets of News Blog 

Saturday, November 19 2022

If you’re used to water mining, having success in the desert might seem challenging— that is until you start thinking of desert ground as a massive sluice box. Many of the principles you’re used to when prospecting and mining in waterways, will translate into desert mining. The most important thing to remember is that water is crucial to gold movement. Unlike a running river or creek with highs and lows, desert placers are much different in that gold is moved quickly during a flash flood, leaving gold stranded as opposed to being moved further by continual water flow in a creek.

During a river high-water event in a non-arid area, gold is moved over a larger area by massive water flows that continue until the water slows as the source dissipates its energy. Spring snow runoff is a good example. Rivers rise and sometimes flood based on the upstream water source. When the snow has melted, the river will slowly get back to  normal. In the desert, gold is moved in the exact same way with the exception that water powerful enough to move gold does so and then just simply stops. In a flash flood, gold is moved very violently and often a very short distance, sometimes percolating into valuable pockets. Here’s where the difference between water and desert mining principles comes into play generally flood gold will concentrate in areas that do not meet the standard thought of inside bends and where the water flow becomes lower.

For the most part, desert mining experts recommend staying out of the washes, gulches and dry river beds— that is unless you clearly see exposed bedrock. Gold will settle fairly quickly when it is trapped behind jagged bedrock and small fault lifts that have not been worn down over time by constant water flow. It IS true you can find areas of concentrated gold-bearing material in the washes, however, the amount of time and energy to get through feet of overburden is usually just not worth it, especially when there are higher values to be found outside of the wash.

Follow the leads out of the wash to where the gold lives in higher concentration. Test and sample areas you see with a great deal of runoff from a tributary coming into the main wash. Here you are only digging through the current flood layer and testing for flood gold. Make your way out of the wash carefully looking at the bottom of the tributary and the areas where the water flowed into the tributary. Look closely for jagged bedrock and slight lifts in the ground and then prospect. Continue to test each of those spots. What started as a few specks of flood gold in the main wash can lead to larger and larger deposits on the flats or in slight inclines across the desert floor. Keep in mind that when a flash flood is dissipating, there is not enough energy to move a lot of rock, but the sand will continue to flow a bit, creating great clues.

In general, cool season precipitation (October through April) is the most extensive source of rain in the desert regions. Rainfall is more widespread and of relatively long duration during the cool season. On the other hand, warm season precipitation (May through September) results largely from short monsoon-type thunderstorms.

If you’re ready to head to a sunnier climate this winter, keep these tips in mind and you just might find enough similarities between water and desert mining to make you return every year.  Good luck!

Posted by: Denise AT 08:51 am   |  Permalink   |  Email
Friday, September 30 2022
In an area either rumored or known to hold gold, where should you look first? The creek, the surrounding hills, washouts, or just where? The characteristics of the gold in that area will help you to know where to start. If the gold is flat and pounded, that indicates it’s been in the water a long time. If the gold is coarse and chunky, you know you’re getting closer to the source. When gold is smoother, stop and go back to the coarsest gold and start working upwards until you find the source.

Keep in mind that gold is gold, so there isn’t necessarily a better type of gold. Some is just easier to recover. There are only two typesgold nugget of gold deposits. The first type is “lode” which is simply everything that is still in the matrix and in the ground, and the other is “placer” —or everything else.

Lode deposits refer to gold that is still locked within its original solid rock formation. This formation of gold generally starts as a vein in rock and is formed over millions of years. Since the gold is locked up in rock, and can be mixed with quartz, calcite, pyrite, and other minerals, lode gold  usually requires specialized mining techniques to extract. Lode mining takes a lot more equipment and generally a lot more expense and is usually undertaken by large commercial operations instead of the average prospector. Placer gold is the gold that most prospectors are more familiar with. Placer gold isn’t really any different than lode gold. It is simply a concentration of that same gold that has eroded and traveled away from the vein.

Since gold is very dense, it will move downhill much slower than the surrounding sediment. It tends to become concentrated on or near the surface of the lode, forming a “residual placer” close to the original bedrock exposure. Gold found downhill from the immediate outcrop above the nearest watercourse is called an “eluvial placer.” Once it reaches the nearest waterway and is transported by flowing water, the gold now is known as “alluvial placer.”  The origin of the dust, flakes and nuggets found by panning and sluicing is usually from a vein up on a nearby mountain.

Bench placers were originally stream placers. Benches are simply where the water used to be, maybe even millions of years ago. They are formed by erosion or geological events such as uplifts, earthquakes or plate drops that changed the stream flow. Some of the most profitable mining is performed on benches. Many benches are highly concentrated by the alluvial deposits that still feed them.

Stream deposits are the last resting place for gold. Once the gold has been released from the lode, gravity and nature does the rest. And unless gold gets stranded on a bench, it will find its way to the water someday. It may take a million years, but it will get there.

When deciding where to begin prospecting, most of the time you’ll want to start panning in a water way, or a wash in the desert where water once flowed. Then let the gold tell you where to go from there. When the gold gets coarse and ragged, start to move up, looking in reverse of how it got to the spot where you found it. In addition to panning and sluicing you may wish to upgrade your mining efforts with a highbanker or power sluice, dredge or trommel. Moving soft soil or river gravel is obviously much easier than breaking rock, but for small scale miners, a rock crusher can pulverize 2 or 3 inch sized rocks into powder in no time. Move more material faster— get more gold! 
Posted by: Denise AT 01:00 am   |  Permalink   |  Email
Saturday, November 27 2021

If you’re ready to head to a sunnier climate this winter to do some desert prospecting, understanding the weather and topography can add to your success. Before loading up and heading to the Southwest, only to be disappointed by bad weather, first check out the weather patterns for the last 60 days and the predicted weather for the next 30-60 days. Why is that important?  Well, it mostly comes down to rainfall— how much and how fast. For example, if there will be a lot of rainfall over an extended time, soils will be loosened and gravity will do its job and cause deeper, and sometimes more concentrated, pay streaks. In general, cool season precipitation (October through April) is the most extensive source of rain in the desert regions. Rainfall is more widespread and of relatively long duration during the cool season. On the other hand, warm season precipitation (May through September) results largely from convective precipitation in the form of short monsoon-type thunderstorms. 

There are three major desert areas that make up the American Southwest:

The roughly 200,000-square-mile Chihuahuan Desert stretches from the southeastern corner of Arizona across southern New Mexico and west Texas to the Edwards Plateau. It runs deep into central Mexico,The Chihuahuan Desert is the most moderate of the three deserts, made up of low and high desert regions and grasslands. It sees the most rain on a regular basis throughout the year with anywhere between 8-12 inches, and areas in New Mexico receive up to 17 inches per year. Unfortunately, because of the Chihuahuan Desert’s higher altitude in southern New Mexico, and the rain patterns there, winter prospecting is a real challenge, especially dry washing. October - March averages 2 inches of rainfall per month, with an average daytime temperature of 55 degrees, making it hard for the ground to dry throughout the season. The pay layer in the Chihuahuan Desert is most likely going to be deeper and more evenly distributed and more highly concentrated than in the Sonoran Desert, but there will be a lot of effort needed to stay on track sampling to find the richest pay layer.

The Sonoran Desert occurs primarily in Mexico. In the USA, most of it can be found in the southern third of Arizona, with small areas in southeastern California.The Sonoran Desert region of Arizona receives between 3-20 inches per year, but these numbers are skewed for the actual low desert gold-bearing region of the state. The Sonoran Desert encompasses a large section of high desert area, ending a few miles south of Prescott, Arizona, following a higher elevation line to the east and west. The normal rainfall in the lower elevation gold-bearing areas of Arizona averages 6 inches annually, all of which falls in about 30 days and includes the monsoons. Yuma is considered the driest area of the state with only 3 inches of rain on average.

The Mojave Desert is primarily in southeastern California and southwestern Nevada, with small portions extending into Arizona and Utah. It has a large amount of high desert elevations and has skewed numbers for the majority of the gold-bearing areas. Lowland areas at less than 1,000 feet elevation average 3.7 inches per year of rain, while Granite Mountain at 4,200 feet above sea level averages 8.5 inches annually. Rich pay layers have been found northwest of Barstow, California by testing and eliminating low to no pay overburden. This area is known for seismic activity with several earthquakes and aftershocks occurring west of the 117 degree meridian, which helps in concentrating gold.


When prospecting in the desert, it’s a good idea to test larger areas in compass headings— testing every few feet north to south to find highest values, then east to west of that spot. Doing so provides you with a line in the desert for further testing. Because of the extended days of rainfall in the Chihuahuan and most of the Mojave compared to the Sonoran Desert, you’ll likely discover a shallow and slightly more compacted layer of good material that is worth processing. However, this “pocket gold” layer can be directly above the really good pay layer you want. Finding gold and digging straight down without continued testing and sampling is not taking advantage of the forces of nature, especially that of water following the path of least resistance and taking the heavies along for the ride. In other words, don’t settle for just any pay layer— follow and use the over burden to get to the BEST pay layer!

If you are planning a desert prospecting trip far in advance, it’s a good idea to start checking weather patterns in April, which is when desert prospecting begins to wind down. That way you will be very prepared when the following fall and winter rolls around. That also gives you time to form a Plan B if the weather is not conducive to your Plan A. If you are a member of Gold Prospectors Association of America (GPAA), there are hundreds of opportunities across the Southwestern states to get on the gold at a GPAA claim. Knowing a little about desert geology is a great start to understanding more about the “why” and “how” gold deposits are formed. And weather is a key factor in knowing “where” gold settles after it breaks from the lode and residuals. Get out there and get your share! Good luck getting the GOLD!

Posted by: Denise AT 07:03 pm   |  Permalink   |  Email
Friday, April 27 2018

A good rule of thumb that most prospectors agree on is to look for placer gold on bedrock and within crevices in the bedrock. This simple principle makes sense— placer gold is heavy and dense and therefore settles at the lowest point as it is pushed around by flowing water. However, gold isn’t always going to make it all the way down to true solid bedrock at the bottom of all gravels. Instead, in certain conditions, it will be found ABOVE bedrock. When these conditions exist, gold will collect on “false bedrock.” For example, a clay layer in streams can act like bedrock and yield more gold than the true bedrock below it. 

bedrock goldAnother situation where gold cannot make it to bedrock is where the streams and gullies have “caliche.” Caliche is a form of cemented gravel often found in desert areas. The gravel is deposited by water flows, just as it would be in any other stream. The difference is that the water contains dissolved calcium salts, and as the water dries up in the streambed, the calcium salts turn into calcium carbonate or calcite. This material gets deposited on the gravel a little at a time and eventually the calcite glues it all together into a solid mass. The solid mass then acts like false bedrock and any new gold flowing across it is stopped in its downward movement by the caliche.

Residual placer gold is formed near the source of the gold and doesn’t really have a chance to work its way downward. Hillside placers are residual placers that are sliding and making their way down the side of a hill into a stream drainage. Gold generally is distributed all through these types of gravels and is not concentrated in any one place. A hillside placer often will be located up above a stream, making it difficult to determine it from a bench placer. Old benches of river gravel can be good places to prospect because they are virgin ground, but because the river used to flow at this location, it’s highly likely that the best gold will be right on bedrock or in crevices of the bedrock. The best way to tell the difference between hillside and bench placers is the shape of the rocks in the gravel. If the gravels and rocks are well-rounded and smoothed, then it’s probably an old river bench. If the gravel is angular, pointy, and sharp, it’s probably a hillside placer that hasn’t yet made its way into a stream.

Another type of placer—the windblown placer— concentrates on the surface, just exactly the opposite of what you would find in a river or stream. The lightest materials such as sand and silt are blown away by the wind. Heavy materials like gold remain behind on the surface. These types of placers are marked by desert pavement, which is a concentration of small to medium-sized rocks that cover the surface and prevent continuing wind erosion. They occur in dry regions with flat terrain, and are often favorite locations of metal detectorists who find nice nuggets at shallow depths.

The next time you find yourself in an environment with well-washed river gravels, you know that the gold will most likely be on the bedrock. But if you find yourself in other types of environments, especially in the desert, consider the possibility that the best gold may actually collect ABOVE it.  Good luck!

Posted by: Denise AT 06:43 pm   |  Permalink   |  Email
Friday, December 29 2017

Given a choice, most miners prefer using water to wash and run material, but in some dry, remote areas that  drwasheris just not feasible. If you focus on the natural conditions that exist in desert regions and work with them, you can maximize fine gold recovery. The number one rule is that the drier the soil, the better. Damp soil conditions are very much a hindrance for drywashers. Beyond that, learning the different soil types you may encounter in the desert and how to deal with them can increase your gold recovery.

Clay is generally known as a great gold robber, making clay-bound gravels the biggest difficulty to overcome. In most of the placers directly derived from weathering lode deposits, the placers are in ravines, gullies and hillsides with sometimes very little gravels and mostly decomposed fragment of rock and fine silt from the decomposing host rock. Host rock containing a lot of feldspars are most problematic. As feldspar breaks down, it creates some difficult clays and silts that bind fine gold to small rocks and sand with the clay and silt particles forming larger clods.

Loamy or sandy conditions are much easier to process with a drywasher than clay-bound material due to the absence of clods and clumps. But if dirt clods are giving you grief, break them down with a large hammer on a canvas tarp, or use a mortar and pestle (dolly pot).

Once you are set up to run material, process in short runs before cleaning out the riffle tray (perhaps after every three 5-gallon buckets). Frequent clean ups minimize the amount of fine gold that may creep or walk down the riffle tray with the tailings. This method uses your dry washer as a form of a classifier to screen off larger material while getting rid of much of the fine silt and lighter weight material.

Re-running tailings can aid in the recovery of lost gold— especially small gold dust and flakes. The second pass through is usually much quicker than the first time because the material has already been classified. With some placers, especially flat, fine gold, rerunning material can be very lucrative. In places where gold is more coarse and angular, very little gold will like be recovered by running the tailings a second time.

You may want to experiment with adding a second layer of cloth to a portion of the riffle tray. Doing so reduces airflow by almost half in that section. In addition to the riffle tray, the void under the riffle tray can collect a sizable amount of really fine gold mixed in with fine silt.

No doubt there are going to be losses of gold when using a drywasher to recover fine gold (20 minus mesh down into the 200 minus gold), but the end goal should be to limit those losses as much as possible and these tips should help.  Good luck!   Learn more about Gold Buddy drywashers here.

Nugget of News Blog

Posted by: Denise AT 02:47 pm   |  Permalink   |  Email
Sunday, December 01 2013

Dry washers are like highbankers except they do not use water to recover gold. While wet processing is nearly always faster and more efficient, especially for fine gold, dry washers are the best tool for recovering gold nuggets, pickers, and flakes from dry materials in the desert or other areas where water is not plentiful.

dry washerDrywashers are operated by shoveling gold-bearing gravels into an upper box which is covered with a screen. The larger rocks that are too big to pass through the screen slide off. Gravel small enough to go through is fed down into the lower gold recovery box, which is an inclined trough with cross riffles much like a sluice. The bottom of the recovery box consists of a thin, light-weight porous cloth. Beneath the riffle box is a blower that pulses air up through the cloth. The vibrations and air flow, combined with the shaking and classifying action of the dry washer allows the gold to settle to the bottom where it is captured in the riffles.

Keep these tips and tricks in mind when using a dry washer:

• Moist soils and clay cause problems, so be sure to crush lumps of clay and dry your dirt in the sun (plastic tarps are ideal) before running through your dry washer. Surface soils might seem dry, but if you dig down a few inches, you may find moisture in the soil that will cause your sand, gravel, and gold to stick together.

• Double-check all the "throw away" rocks. Scanning them with a metal detector is a great way to ensure you're not tossing aside gold-laden rocks. Also, don't assume old tailings piles have been totally worked out. This is  another time to use a metal detector because ordinary rocks could be  laced with gold and completely over-looked by earlier prospectors.


• Consider using a dry gold vacuum to clean out crevices in bedrock. Feed the material that you sucked up into your vacuum bucket into your dry washer.


• Drywashing can be a very dusty process, so try to stay upwind as much as possible and wear a dust mask.
• Do a clean up every couple of hours, or after processing roughly one to two yards of material.

Looking for a drywasher? The Gold Buddy brand is available in 4 sizes and also check out the new heavy duty
Gold Storm dry washer. Whichever you choose, SAVE $10 with coupon code TAKETEN at check out. Offer expires Dec. 31, 2103.

Posted by: Denise AT 06:14 pm   |  Permalink   |  0 Comments  |  Email
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