Author Topic: The Science of Stream Deposition  (Read 18540 times)

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benvalmores

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Re: The Science of Stream Deposition
« Reply #15 on: November 30, 2010, 11:31:04 PM »
thanks Raqs...


benvalmores

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Re: The Science of Stream Deposition
« Reply #16 on: November 30, 2010, 11:35:27 PM »
DEFINING ACCEPTABLE GROUND
 
By Dave McCracken

   5th of a series

It is a very good idea for you to define for yourself what amount of gold is minimally acceptable for you to recover on a daily basis. It might be a half-ounce per day. It might be more. Or it might be less, depending upon the size of the dredging or other mining equipment you are using, your operating expenses, and how much gold you need to recover to make the effort worthwhile. The main point here is that you should set some minimum standard. If you are recovering that much gold on a daily basis, you will stick with it. If your daily averages start dropping below that point, you will start sampling around for better ground.

There are several good reasons for doing this. One is that if you do not know about how much gold is acceptable to you, and what is not acceptable, you can waste a lot of time "going on hoping" (for some undefined target) while you continue to dredge in low-grade material, rather than  sample around for something better like you should. Another good reason is that you need to determine how far to each side and how far to the rear to dredge into the lower-grade material along the boundaries of a pay-streak. I covered this subject more thoroughly in another article.

Perhaps the best reason that you need to define a minimum acceptable level of daily gold for yourself, is so you can take in the better, and much better, and tremendously-better pay-dirt as a bonus when you find it. This could be on a regular basis if you become good at sampling. If you do not take on the good finds as a bonus, you can find yourself comparing the good finds with the acceptable finds; and pretty soon the acceptable finds may not be acceptable any more! This is especially true when you are  dredging up a high-grade pay-streak.

 

I know of a guy that was new to gold dredging, who was into a very large pay-streak which was paying him a little more than half-ounce per day for every day that he went out and dredged. He was happy with this. That was well more than an average day's wages in the profit he was making over top of expenses, and gold prices have been going up to make that even better. Everything was going along just fine until one day when he uncovered a bedrock up-cropping and pulled six ounces of beautiful gold out of a single pocket in the bedrock just in that one day. The following day, he was back into the half-ounce amounts again. Only that was no-longer good enough. He quit shortly thereafter. He left the area, never came back, and I have not heard of him since.

What happened? He got spoiled from the incredible feelings generated from uncovering really valuable golden treasure. This causes something which is often referred to as  "gold or treasure fever." Once the extreme high-grade was finished, he could not go back to recovering just half-ounce of gold per day, anymore. It is kind of like losing the person you love. Nobody else will do.

If you stick with gold prospecting long enough to get good at sampling, there will always be greater highs. But if the greater highs are the only thing that is now acceptable pay-dirt, you will find yourself frustrated a lot of the time.

If you define for yourself what is acceptable as pay-dirt, as you continue to get better at sampling, you will find that there is a surplus of acceptable ground available to you. Therefore, you will be able to upgrade your minimum acceptable levels a degree or two as time goes along.

If you are willing to mine every bit of acceptable ground that you can get into, and are willing to accept the bonuses as they are uncovered, and just treat them as a bonus, you will be making more gold more of the time - and you will find more bonuses, too

benvalmores

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Re: The Science of Stream Deposition
« Reply #17 on: November 30, 2010, 11:41:51 PM »
GOLD PANNING INSTRUCTIONS
By Dave McCracken
 
"The Gold Pan as a Production Tool"
   
The main thing to remember about the use of a gold pan is that while it is very effective as a gold-catching device, it can only process a limited volume of streambed material. For this reason, the gold pan is normally not used as a production tool in commercial use, other than in the most remote locations where it would be very difficult to haul large pieces of equipment, and where there is only a small amount of streambed material present -- which is paying well enough to make the panning worthwhile.

The gold pan is most commonly used to locate a richer paying area by sampling, so that larger production equipment can be brought into that location to work the ground to recover more gold.

There are stories in the old mining records about the ground being so rich during the 1849 gold rush that as much as 96 ounces of gold were recovered from a single pan. That is $100,000+ at today’s rate of exchange, and must have been some very rich ground indeed!

Stories like that are rare and pay-dirt like that is not run across very often. However, it is not too uncommon to hear of prospectors today who are able to consistently produce better than an ounce of gold per week with a gold pan in the high country, and have the gold to show for it. Some do better, but these prospectors have usually been at it for awhile and have located hot spots. I personally know of two guys who support themselves with a gold pan, and one of them lives pretty well. As mentioned earlier, the gold pan gives you unlimited accessibility, and these prospectors look around to find the pockets in the exposed bedrock along the edges of the creek-beds in their areas, picking up a few pieces here, a few there, and a little pocket of gold once in awhile. It adds up, and to them it is better than punching a time clock.

 Placer Geology

There is still plenty of rich ground to be found in gold country if you are willing to do the work involved in finding it.
Gold Panning Procedure

Panning gold is basically simple, once you realize that you are doing the same thing that the river does when it causes gold to concentrate and deposit during flood storms.

The process basically consists of placing the material that you want to process into your pan and shaking it in a left to right motion underwater to cause the gold, which is heavy, to work its way down toward the bottom of your pan. At the same time, the lighter materials, which are worthless, are worked up to the surface of the gold pan where they can be swept away. The process of shaking and sweeping is repeated until only the heaviest of materials are left-namely the gold and heaviest black sand.

Once you are out in the field, you will notice that no two people pan gold exactly alike. After you have been at it awhile, you will develop your own little twists and shakes to accomplish the proper result.

Here follows a basic gold panning procedure to start off with which works well and is easy to learn:

STEP 1: Once you have located some gravel that you want to sample, place it in your gold pan-filling it about 3/4 of the way to the top. After you have been at it awhile, you can fill your pan to the top without losing any gold. While placing material in your pan, pick out the larger-sized rocks, so that you can get more of the smaller material and gold into the pan.

Panning One

STEP 2: Choose a spot to do your panning. It is best to pick a location where the water is at least six inches deep and preferably flowing just enough to sweep away any silty water that may be washed from your pan. This way, you can see what you are doing better. You do not want the water moving so swiftly that it will upset your panning actions. A mild current will do, if available.

It is always best to find a spot where there’s a rock or log or stream-bank or something that you can sit down upon while panning. You can pan effectively while squatting, kneeling or bending over, but it does get tiresome. If you are planning to process more than just one or two pans, sitting down will make the activity much more pleasant.

STEP 3: Carry the pan over to your determined spot and submerge it underwater.

STEP 4: Use your fingers to knead the contents of the pan to break it up fully and cause all of the material to become saturated with water. This is the time to work apart all the clay, dirt, roots, moss and such with your fingers to ensure that all the materials are fully broken up and in a liquid state of suspension whithin the pan.

The pan should be underwater while doing this. Mud and silt will float up and out. Do not concern yourself about losing any gold when this happens. Remember: gold is heavy and will sink deeper in your pan while these lighter materials are floating out and away.

Panning Two

STEP 5: After the entire contents of the pan have been thoroughly broken up, take the pan in your hands (with cheater riffles on the far side of the pan) and shake it, using a vigorous left and right motion just under the surface of the water. This action will help to break up the contents of the pan even more and will also start to work the heavier materials downwards in the pan while the lighter materials will start to surface.

Be careful not to get so vigorous in your left and right shaking that you slosh material out of the pan during this step. Depending upon the consistency of the material that you are working, it may be necessary to alternate doing steps four and five over again a few times to get all of the pan’s contents into a liquid state of suspension. It is this same liquid state of suspension that allows the heavier materials to sink in the pan while the lighter materials emerge to the surface.

STEP 6: As the shaking action causes rocks to rise up to the surface, sweep them out of the pan using your fingers or the side of your hand. Just sweep off the top layer of rocks which have worked their way up to the pan’s surface.

Panning Three

Don’t worry about losing gold while doing this, because the same action which has brought the lighter rocks to the surface will have worked the gold deeper down toward the bottom of the pan.

When picking the larger rocks out of the pan, make sure that they are clean of clay and other particles before you toss them out. Clay sometimes contains pieces of gold and also has a tendency to grab onto the gold in your pan.

Note: Working the raw material through a classification screen into the gold pan during Step 1 or Step 3 will eliminate the need to sweep out larger rocks in Step 6. This will also allow you to pan a larger sample of the finer-sized material(which contains all the gold you will find in a pan sample).

Panning Four

STEP 7: Continue to do steps five and six, shaking the pan and sweeping out the rocks and pebbles(if present), until most of the medium-sized material is out of your pan.

STEP 8: Tilt the forward edge of your pan downward slightly to bring the forward-bottom edge of the pan to a lower position. With the pan tilted forward, shake it back and forth using the same left and right motion. Be careful not to tilt the pan forward so much that any material is spilled over the forward-edge while shaking.

This tilted shaking action causes the gold to start working its way down to the pan's forward-bottom edge, and continues to work the lighter materials to the surface where they will be more easily swept off.

STEP 9: Carefully, by using a forward and backward movement, or a slight circular motion just below the surface of the water, allow the water to sweep the top layer of worthless, lighter materials out of the pan. Only allow the water to sweep out a little at a time, while watching closely for the heavier materials to be uncovered as the lighter materials are swept out. It takes some judgment in this step to determine just how much material to sweep off before having to shake again so that no gold is lost. It will just take a little practice in panning gold before you will begin to see the difference between the lighter materials and the heavier materials in your pan. You will develop a feel for knowing how much material can be safely swept out before re-shaking is necessary. When you are first starting, it is best to re-shake as often as you feel that it is needed to prevent losing any gold. When in doubt, shake! There are a few factors which can be pointed out to help you with this. Heavier materials are usually darker in color than the lighter materials. You will notice while shaking the pan that it is the lighter-colored materials that are vibrating on the surface. You will also notice that as the lighter materials are swept out of the pan, the darker-colored materials are uncovered.

Panning Five

Materials tend to get darker (and heavier) as you work your way down toward the bottom of the pan, where the darkest and heaviest materials will be found, they being the purple and black sands, which are usually minerals of the iron family. The exception to this is gold, which is heaviest of all. Gold usually is of a bright and shiny metallic color and shows out well in contrast to the other heavier materials at the bottom of the gold pan.

One other factor to keep in mind is that the lighter materials sweep out of your pan more easily than do the heavier materials. As the heavier materials are uncovered, they are increasingly more resistant to being swept out of the pan, and will give you an indication of when it is time to re-shake.

As you work your way down through your pan, sometimes gold particles will show themselves as you get down to the heavier materials. When you see gold, you know it is time to re-shake your pan.

Panning Six

There is another popular method of sweeping the lighter materials out of the top of your pan which you might prefer to use. It is done by dipping your pan under the water and lifting it up, while allowing the water to run off the forward edge of the pan, taking the top layer of material along with it.

STEP 10: Once the top layer of lighter material is washed out of your pan, re-shake to bring more lighter materials to the top. By "lighter materials," I mean in comparison to the other materials. If you continue to shake the lighter materials to the top and sweep them off, eventually you will be left with the heaviest material of all, which is the gold. It does not take much shaking to bring a new layer of lighter material to the surface. Maybe 5 or 6 seconds of shaking will do it, maybe less. It all depends upon the consistency of the material and how much gold is present.

Continue to pluck out the larger-sized rocks and pebbles as they show themselves during the process.

STEP 11: Every few cycles of sweeping and re-shaking, tilt your pan back to the level position and re-shake. This keeps any gold from being allowed to work its way up the forward-edge of your pan.

STEP 12:Continue the above steps of sweeping and re-shaking until you are down to the heaviest materials in your pan. These usually consist of old pieces of lead and other metal, coins, BB's, old bullets, buckshot, nails, garnets, small purple and black iron rocks, and the heavy black sand concentrates. Black sands consist mainly or in part of the following: magnetite (magnetic black sands), hematite (non-magnetic black sands), titanium, zircon, rhodolite, monazite, tungsten materials, and sometimes pyrites (fool's gold), plus any other items which might be present in that location which have a high specific gravity-like gold and platinum.

Once down to the heaviest black sands in your pan, you can get a quick look at the concentrates to see how much gold is present by allowing about a half-cup of water into the pan, tilting the pan forward as before, and shaking from left to right to place the concentrates in the forward-bottom section of your pan. Then, level the pan off and swirl the water around in slow circles. This action will gradually uncover the concentrates, and you can get a look at any gold that is present. The amount of gold in your pan will give you an idea how rich the raw material is that you are sampling.

Panning Seven

A magnet can be used to help remove the magnetic black sands from the gold pan. Take care when doing this. While gold is not magnetic, sometimes particles of gold will become trapped in the magnetic net of iron particles which clump together and attach to the magnet. I prefer to drop the magnetic sands into a second plastic gold pan, swish them around, and then pick them up once again with the magnet. Depending upon how much gold this leaves behind, I might do this several times before finally discarding the magnetic sands.

Many beginners like to stop panning at this point and pick out all the pieces of gold (colors) with tweezers. This is one way of recovering the gold from your pan, but it is a pretty slow method.

Most prospectors who have been at it for awhile will pan down through the black sands as far as they feel that they can go without losing any gold. Then they check the pan for any colors by swirling it, and pick out any of the larger-sized flakes and nuggets to place them in a gold sample bottle. Then the remaining concentrates are poured into a small coffee can or bucket and allowed to accumulate there until the end of the day, or week, or whenever enough concentrates have been collected to make it worthwhile further process them. This is really the better method if you are interested in recovering more gold, because it allows you to get on with the job of panning and sampling without getting deeply involved with a pair of tweezers. Otherwise, you can end up spending 25% of your time panning and up to 75% of your time picking out small colors from the pan!
Panning Down All The Way To Gold

It is possible to pan all the way down to the gold-with no black sands, lead or other foreign materials remaining in the pan. This is often done among prospectors when cleaning up a set of concentrates which have been taken from the recovery system of a larger piece of equipment-like a sluice box or suction dredge.

Panning all the way down to gold is really not very difficult once you get the hang of it. It is just a matter of a little practice and being a bit more careful. When doing so, most prospectors prefer to use the smooth surface of the gold pan, rather than using the cheater riffles. The key is to run the concentrates through several sizes of classification screens and pan each size-fraction separately. Use of a smaller-sized pan ("finishing pan") makes this process go easier.

When panning a set of concentrates all the way down to the gold-or nearly so, it is good to have a medium-sized funnel and a large-mouthed gold sample bottle on hand. This way, once you have finished panning, it is just a matter of pouring the gold from your pan into the sample bottle through the funnel. Pill bottles and baby food jars can make good gold sample bottles for field use, because they are usually made of thick glass and have wide mouth. Plastic bottles are even safer.

Another method is with the use of a gold snifter bottle. This is a small hand-sized flexible bottle with a small sucking tube attached to it. Squeezing the snifter bottle creates a vacuum inside. Submerged gold from the pan can consequently be sucked up through the tube.

If you do not have a snifter bottle or funnel, try wetting your finger with saliva and fingering the gold into a container, which should be filled with water. The saliva will cause the gold and concentrates to stick to your finger until it touches the water in the container. This works, but the funnel method is faster.


Practice Gold Panning

If you are not in a known gold-producing location, but want to do some practice panning to acquire some skills before going out into the field, you can practice in your own backyard. Use a washtub to pan into and some diggings from your garden (or wherever) to simulate streambed materials. I recommend that you throw in some rocks and gravel along with the dirt so that it takes on an actual streambed consistency. Take some pieces of lead, buckshot or small lead fishing weights, cut them up into various sizes ranging from pellet-size down to pinhead-size, and pound some of them flat with a hammer. This puts the pieces of lead in the same form as the majority of gold found in a streambed-flake form. They will act in much the same way as will flakes and grains of gold. Leave a few of the pieces of lead shot so that gold nuggets can also be simulated.

When panning into the tub, place some of these pieces of lead into your pan, starting off with the larger-sized pieces first. Keep track of how many pieces of lead you use each time so that you can see how well you are doing when you get down to the bottom of the pan. Practice panning in this manner can be very revealing to a beginner, especially when he or she continues to put smaller pieces of lead into the pan as progress is made.

If you can pan small pieces of lead successfully, then you will not have much difficulty panning gold (higher specific gravity) out of a riverbed. And, who knows? You may end up with gold in your pan-right out of your own backyard! It wouldn't be the first time.


benvalmores

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Re: The Science of Stream Deposition
« Reply #18 on: November 30, 2010, 11:49:33 PM »
DIGGING FOR GOLD
By Dave McCracken
 
Experienced gold miner lays out fundamentals of running a successful surface prospecting program.

             The Sluice Box
             Sluicing & Highbanking
            High-bank Operation
            Operating A Highbanker
   

A "sluice box" is a trough-like gold recovering device which has a series of obstructions or baffles, called "riffles", along its bottom edge. While a steady stream of water is directed to pass through, streambed material is shoveled into the upper-end of the box. The flow of water washes the streambed materials through the sluice and over the riffles, which trap the gold out of the material.

The reason a sluice box works is that gold is extremely heavy and will work its way quickly down to the bottom of the materials being washed through the box. The gold then drops behind the riffles and remains there, because there is not enough water force behind the riffles to sweep the gold out into the main force of water again.

A sluicing operation, when set up properly, can process the gold out of streambed material about as fast as it can be shoveled into the box. This can be many times more material than a panning operation can handle, yet with similar efficiency in gold recovery. How much material can be shoveled into a sluice box greatly depends upon the consistency and hardness of the material within the streambed itself, and how easily it can be broken away.

A sluice requires a steady flow of water through the box to operate at its best efficiency. Most often, the box is placed in a stream or creek where water is moving rather swiftly, with the sluice being placed in such a way that a stream of water is directed through the box.

Sluice Box Placement

In locations where water is available, but is not moving fast enough to be channeled through the box for sluicing purposes, the water can be pumped or siphoned to the box with excellent results (covered later). How much water is available, and whether or not it will need to be transported to your sluice box, is something that needs to be considered during the planning stages of a sluicing operation.

Because so much more material can be processed with a sluice, than with a gold pan, streambed materials which contain far less gold values can be mined while recovering just as much or more gold. Therefore, if the streambed material had to pay a certain amount in gold values in to be worked with a gold pan to your satisfaction, gravel containing only a fraction of as many values can be worked with the same result using a sluice box. This is an important factor to grasp; because it means the modern sluice box opens up a tremendous amount of ground that can be profitably mined by an individual.

Motorized sluicing (also often called "high-banking") is an activity similar to sluicing, except that sluicing is almost always accomplished with the water-flow from the creek or river keeping gravel moving through and over the riffles. As demonstrated in the following video sequence, a motorized sluice (also called a "hydraulic concentrator") is usually set up with a water pump that supplies water for the sluice box:

The Hydraulic Concentrator

Rip in the Field

Motorized sluices are usually equipped with a recovery system that is set up with adjustable-length legs. This allows the box to be adjusted from side to side and front to back on uneven ground. This allows the water flow to be created for optimum gold recovery. Most motorized sluices available on today's market also include a screening device over the top of the feed-section of the sluice box. Screening the larger-sized rocks out of material to be sluiced is one of the primary methods for improving fine (small) gold recovery. Any time you can screen larger rocks out, you can slow the water down through the sluice, which will allow even smaller particles of gold to become trapped inside the riffles.

In normal sluicing, the operators must find a location alongside of a creek or river where the water is flowing just right, at the proper depth, to set up the sluice so the proper amount of water can be directed through. Once the sluice is set up, gold-bearing material must be carried to the sluice, screened separately, and carefully fed through the sluice box.

With a motorized sluice, all you need is a supply of water within several hundred feet of where you want to dig. The screen and sluice assembly can be set up directly at the work site so that pay-dirt can be shoveled directly onto the screening section. The pump/engine assembly will pump water from the water source, through a pressure hose, to the sluice.

Another advantage to the motorized sluice is that in some areas today, it is not legal to wash silt directly from the bank into an active waterway. With a motorized sluice set up some distance from the stream or river, you have an opportunity to utilize natural contours up on the land to slow the water down enough to allow the sediments to settle before (if ever) the water re-enters the creek or river.

SAMPLING

Just like in any other type of gold mining activity, the key to doing well is in digging sample holes to first find a high-grade gold deposit.

 Placer Geology

In many places, there is more gold up on the banks than you will find in the river. This can sometimes be true on the Klamath River in northern California. Actually, it is not only that there is more gold on the banks than in the river. The gold on the banks can sometimes just be easier to get at for a small operation.

What happened along the  River, and in many other areas, is not difficult to understand. The old-timers started mining down in the creek or river, and moved uphill, allowing gravity to carry the water and tailings back down towards the creek or river. As the old-timers worked further up into the banks, often the gravel became deeper and more difficult to remove by conventional hand methods. In time, the old-timers developed hydraulic mining. This is where they directed large volumes of water from nearby (or sometimes distant) creeks under great pressure through monitors (huge pressure nozzles). The high-pressure water was used to wash large volumes of gravel through large sluice boxes placed on the banks of the creeks and rivers. As the sluicing operations cut further up into the banks, the sluice boxes were moved forward, which left tailings deposited on the banks.

It is estimated that as much as 50-percent of the gold washed right through the sluice boxes in hydraulic operations because of the large volume and velocity of water which such operations used. Hydraulic operations did not lose gold in the same amounts all of the time. Much of the gravel that these operations processed contained little or no gold. The concentrations of gold were found along bedrock or at the bottom of lower strata flood layers. So, valueless top-gravels were processed at volume speed, and they would try to slow down when getting into pay-dirt materials. Sometimes, however, they would cut into pay-dirt materials at volume speed--before having a chance to slow down. This is where large volumes of gold would wash directly into the tailing piles.

Since the time of large-scale hydraulic mining, there have been several occasions of extreme high water. The 1964 flood in the western United States is one example. Floods of such magnitude, all throughout gold country, re-deposited old hydraulic tailings piles into newly-formed streambeds up on the banks and within the active waterways. Places where gold was lost from hydraulic operations formed into new pay-streaks--often only inches or a few feet from the surface. This is true all up and down the banks of the Klamath River--and probably many other rivers as well--which has created a wonderful and exciting opportunity for modern small-scale gold miners.

Contrary to popular belief, many pay-streaks today are not found down along the bedrock. In fact, many of the pay-streaks surface miners are finding along the Klamath River are situated in a flood layer (1964 flood) within two feet of the surface. This flood layer is often resting directly on top of undisturbed hydraulic tailings.

We are also finding similar pay-streak deposits inside the active river with the use of suction dredges.

Finding pay-streaks with a surface digging project is usually done by setting up the sluice in several different locations, and giving each sample a large enough test hole to obtain an idea of how much gold the gravel is carrying. Sample holes should be taken to bedrock if possible. However, if the gravel goes deep, you have to avoid getting in too far "over your head." At the point where you start digging deeper than 3 or 4 feet with a pick and shovel, any pay-streak is going to have to be exceptionally rich to make the effort worthwhile. Richer deposits are more scarce; and therefore more difficult to find. So it is important to stay within effective digging/sampling range, and not get yourself into a full-scale production operation before you have found a high-grade gold deposit.

Sometimes you can learn valuable information before you start sampling. If other miners in the immediate area are finding gold deposits along a specific flood layer, you should be sampling for gold along the same flood layer while digging around in the nearby vicinity. Gathering information such as this is one of the many benefits of belonging to an active mining club or association. Active mining organizations will include others who are actively pursuing the same type of mining activity that you are engaged in.

While sampling with a pick and shovel, it is very seldom that you will actually see gold in the gravel as it is being uncovered. Usually, you do not see the gold until it is time to clean-up the sluice box after the sample is complete.

Sluice Box Clean-up

If you finish a sample hole and end up with a good showing of gold, the next step is to find out exactly where the gold came from. In other words, did it come off the bedrock, or did it come from a particular layer in the streambed? You must know where the gold is coming from to evaluate the value of the pay-streak. For example, digging two feet into a paying flood layer requires much less time and effort than digging four feet and having to clean rough bedrock. If you do not know for certain where the gold is coming from, and you assume it is coming from the bedrock underneath four feet of hard-packed streambed, you might decide it is not rich enough to work and walk away from a very rich deposit located at the two-foot flood layer

At the same time, if you are able to reach bedrock, you always want to get a good sample there by thoroughly cleaning the surface and any irregularities there. Sometimes that is where the richest deposits are found.

Thoroughly Cleaning Bedrock

Pinpointing the source of gold is reasonably easy once the sample hole has been opened up. It is likely that the gold will be concentrated either along the bedrock, along the bottom of a flood layer, or at both locations. Sometimes, there is more than one flood layer that carries gold. You can run small production samples of each stratum separately to see which is paying. Or, sometimes you can simply take pan-samples in the different contact zones between the layers

Some pick & shovel miners are using metal detectors in their prospecting activities. Some of the new gold metal detectors will sound out on pieces of gold as small as the head of a pin! But in gravel deposits, metal detectors can also be used quite well to locate the concentrations of magnetic black sand. Black sand tends to concentrate in pay-streaks, just like gold. Therefore, locations sounding out heavy concentrations of magnetic sand on metal detectors are excellent places to follow up with pick & shovel sampling.

One question commonly asked about sluicing procedure is the proper slope-setting for a sluice box. A sluice box generally requires about an inch drop per each linear foot of sluice. This is just a guideline. Basically, you need enough water velocity to keep the material active in the sluice behind the riffles, but not so much that you are washing most of the material out from behind the riffles. I like to get enough water flow to keep the larger material moving through and out of the box. If I see lots of rocks building up in the sluice, I know I do not have enough water velocity. An occasional rock needing to be helped along is alright in a sluice (although maybe not a dredge sluice!). In surface sluicing (non-dredging), I would rather toss out an occasional rock and have the peace of mind that I am also achieving maximum possible fine gold recovery.

Working the Sluice Box

A common practice in sluicing is to also to set up a second sluice behind the primary sluice. The plastic Le’Trap sluice works exceptionally well for this because it recovers fine gold so well, and for its ease in cleanup. The idea is to have a safety check on your primary recovery system to make sure it is working properly.

And if all else fails, you can always do some pan-testing in your tailings to see if  your sluice might be losing any gold.

One mistake that beginners often make is in thinking that the recovery system is at fault because they are not recovering very much gold. Most often, however, it is not the recovery system. It is the lack of a good-paying pay-streak! The answer to this is to hustle around with more sampling. Ask around to see what and where it is working well for others in the area. Use their operations as a model.

Flood layer pay-streaks are often easier than bedrock pay-streaks to clean up with pick & shovel surface mining operations. There are several reasons for this. One is that a flood layer pay-streak is closer to the surface. This means less gravel to shovel to reach the gold. Another reason is that it takes more effort to clean the gold off of a bedrock surface when you are not using a dredge. You can only do so much with a shovel. After that, you must resort to a whisk broom and/or a  motorized vacuum cleaner. This is why portable dry land dredges are also becoming so popular. They give you the ability to clean bedrock surfaces and cracks with minimum effort. If the gold is coming off bedrock, you must invest the extra effort to clean it off well. Otherwise, you stand the chance of leaving an important portion of the gold behind as you mine forward on the pay-streak.

Many pick & shovel miners today also are equipped with an optional suction attachment. To use it, the pressure hose from the water pump is attached to a suction nozzle that directs the water and material through a suction hose into the sluice. So after an initial hole is dug up out of the water, the hole can be filled with water and material can be sucked into the sluice box. The recovery system can be positioned so that the water discharge can run back into the hole-- keeping the hole from running out of water.

So you can dig a hole up on the land, and then begin a suction mining operation outside of the active waterway. This is great!

In California, dredging permits are only required when dredges are operated inside of the active waterway. Therefore, my personal understanding is that suction miners up on the land are not required to have a dredging permit as long as they are not dredging inside the active waterway.

Some surface miners also sample for the gold-path up on the bank by pan sampling the moss. Sometimes, how well the moss is producing gold at the surface can also be an indication of how well the gravel is paying underneath.

When moss, roots, clay and other types of materials are producing good quantities of gold, it is always a good idea to break up the material as much as you can before running it through a sluice box. This is usually done by pulling it apart over the top of a classification screen, or breaking it up inside a bucket of water before running it through the sluice. This slows down production, so the additional work must be rewarded by the recovery of more gold.

Once you find a pay-streak in pick & shovel mining, you want to give some thought to how you are going to develop the deposit with a minimum of wasted effort. For example, you will have to pile the cobbles (rocks too large to pass through your recovery system) and tailings somewhere. Preferably, cobbles and tailings would not be placed upon some other section of the pay-streak. Otherwise they might need to be moved twice, or you might be forced to leave behind high-grade areas that have been further buried. So it is worth some extra sampling to get an idea of the pay-streak's boundaries. Then you can deposit the tailings material in a location where you will not need to move them again.

Placing tailings is, and always has been, one of the most important aspects of a mining operation--of any size. Yet, it is one of the most neglected aspects of mining by a substantial portion of small-scale miners. In fact, we have a standing principle, true as it may be, along the Klamath River: "Dowsing works: just look where a successful pick & shovel miner or dredger has been throwing his or her cobbles. It is almost guaranteed there will be excellent gold underneath!"

This usually comes back to a simple case of gold fever. The miner starts getting a good showing of gold, gets excited, and never slows down to define the boundaries of the deposit. This almost guarantees an important portion of the deposit will end up underneath cobbles.

Pay-streaks up out of the water are often different from those found in the river or creek. What I mean by this is that they do not always follow the same gold path. When you find a pay-streak in the river, you can usually line it up with the next river bend and make a pretty fair guess where the next several pay-streaks are likely to be. This is because river pay-streaks usually form from gold that has washed down the river along its own gold path during major flood storms.

Pay-streaks outside of the river often were formed from gold out of tailings from old hydraulic mining operations. So you can find a small pay-streak up on the bank, follow it until it plays out, and then not find any sign of it further upstream. This is because the source of the gold deposit was not from a point further up river. Then you can find another pay-streak on another path altogether. In other words, pay-streaks up on the bank might not follow a specific single gold path, as they usually do in the river.

Pick & shovel mining is a lot of fun - when you are finding gold. A healthy portion of our miners along the Klamath River mine out of the water. The reason for this is that it gives them an opportunity to find pay-streaks without having to commit to an underwater dredging operation.

Watch out--the biggest challenge in gold mining is not in finding the gold; it is getting over the “fever” after you have found it!

benvalmores

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Re: The Science of Stream Deposition
« Reply #19 on: December 01, 2010, 12:04:59 AM »
HOW TO CREVICE FOR GOLD

By Linda Montgomery

I have found it is not necessary, during weekend or vacation gold mining trips, for women to be resigned to the camp cook and dish washer position. There is an easy, hassle-free way to spend your time and have it turn out uniquely rewarding at the end of the day. This method is called "crevicing". It requires few tools, no back breaking work and can be enjoyed by the whole family. My kids and I have creviced in desert dry washes as well as along streams and rivers. The final panning of the material we've recovered has always kept us going back for more!

Crevicing gets it's name from the cracks and crevices found in exposed bedrock. These are known gold-catching areas. It is amazing how deep gold can settle inside these cracks. The job of crevicing involves breaking the crack open wide enough to allow you to get out all the material that it contains. This isn't hard. Within a short time you can become a pro at it. The tools of the trade vary. it's best to have a chisel, rock pick and a gold claw. A bucket is needed to put your material in, along with a #4 classifier. If you classify at your work site, you will not have such a heavy load to lug back to camp. Add a tablespoon to your tools for scooping out material in places where your hand won't fit.

The very best piece of equipment you can add to your operation is one of the several models of motorized vacuum suckers now available on the mining market. It is not a necessity, but there is no comparison to the ease and thoroughness of using one. These vack machines are extremely lightweight and strap to a pack frame for carrying on your back. Instead of spooning or scraping out your material, you can simply vacuum it up. These motorized vacuums are also good for sucking flood gold out of moss on high water rocks. This is probably the easiest job of all.

But do not fret, if you don't have one. When I started crevicing, I used a hammer and a screwdriver!

After you've gathered your tools together, hike up the river or along a dry wash, wherever you happen to be. Look for low bedrock exposure, because gold is heavy it tends to concentrate more readily in the low spots. Preferably find a crevice in the rock running toward the river instead of along it. These usually catch more gold. Remember also, the bigger the crack, the larger the gold that could be trapped inside.

Start working by loosening everything inside the crevice with your gold claw or screwdriver. Scrape it out and into your classifier on top of your bucket. Chip around any rocks jammed in the way with your chisel until they come free and you can pull them out. Sometimes you can knock off the sides of the crack to widen it by hammering. This enables you to work farther and deeper into the crevice. If you reach a point where you cannot fit your hand, use your spoon; scraping away until the crevice is clean.

This type of bedrock is over 500 million years old. It's origins come from the ancient mountains that used to be here. Quite often it appears harder than it is; but if you keep digging and scraping, it is actually soft enough to keep breaking away.

Take everything! Moss, sand, dirt, anything that you can loosen. Clean the crevice out as much as possible or as far as you can reach. If you finish one spot and have not gathered enough material in your bucket, move to another spot.

The hardest part about this whole method of mining is carrying your material back to camp. You can regulate this to suit you. Or, if you have kids or a partner, you can share the load. That is, unless water is near the place where you are working. In that case, you can either pan or sluice your pay-dirt right there.

Crevicing is fun and rewarding for the whole family. You will probably recover lots of fine gold and once in awhile a nice nugget or two. Your back will not hurt and you will not be dog tired when you are through, either! If suction dredging for gold is not your cup of tea, and you do not want to spend extra dollars on other equipment, crevicing may be just the thing for you. No noisy engines, no gas to haul, nothing to break down. Just peace and quiet, and the enjoyment of a job well done.

benvalmores

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Re: The Science of Stream Deposition
« Reply #20 on: December 01, 2010, 12:07:53 AM »
ALL THESE WILL BE SUPPORTED BY PICS AND ILLUSTRATIONS ONCE THE ATTACHMENT PROBS WILL BE CORRECTED

Offline Ben Valmores

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Re: The Science of Stream Deposition// MY YEAR ENDER VIDEO...
« Reply #21 on: December 31, 2012, 09:27:19 AM »
See it on you tube,

THE ART OF MINING, Hardrocking & Alluvial mining in Compostela Valley & Kiblawan Philippines

http://www.youtube.com/watch?v=duZiaZuN27c
“Destiny is not a matter of chance. It is a matter of choice: It is not a thing to be waited for, it is a thing to be achieved.”
---William Jennings Bryan

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Re: The Science of Stream Deposition// MY YEAR ENDER VIDEO...
« Reply #22 on: December 31, 2012, 12:34:19 PM »
See it on you tube,

THE ART OF MINING, Hardrocking & Alluvial mining in Compostela Valley & Kiblawan Philippines

http://www.youtube.com/watch?v=duZiaZuN27c

I'm here in California now so when I clicked on that link I get the following message;
This video contains content from The Harry Fox Agency, Inc. (HFA) and EMI, one or more of whom have blocked it in your country on copyright grounds.

Offline Ben Valmores

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Re: The Science of Stream Deposition
« Reply #23 on: December 31, 2012, 06:55:43 PM »

Yes Admin,
It's about the soundtrack that i used Depeche Mode's "Gold" tune.
I have clear acknowledgement about the soundtrack, that no intentions of copyrights infringement is being meant.
The video definitely is mine, i just found it relevant to incorporate the tune "Gold" since the videos and photos talks about Gold.
Well, its sad that even with complete acknowledgement about the song, they still ban it in some countries like yours.
Maybe i'll just have a "local" someone sing the "Gold" tune to incorporate it to my videos.
anyways thanks for the note.
I'll make another video with some alternative local soundtrack then.
“Destiny is not a matter of chance. It is a matter of choice: It is not a thing to be waited for, it is a thing to be achieved.”
---William Jennings Bryan

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Re: The Science of Stream Deposition
« Reply #24 on: January 02, 2013, 09:33:27 AM »

Yes Admin,
It's about the soundtrack that i used Depeche Mode's "Gold" tune.
I have clear acknowledgement about the soundtrack, that no intentions of copyrights infringement is being meant.
The video definitely is mine, i just found it relevant to incorporate the tune "Gold" since the videos and photos talks about Gold.
Well, its sad that even with complete acknowledgement about the song, they still ban it in some countries like yours.
Maybe i'll just have a "local" someone sing the "Gold" tune to incorporate it to my videos.
anyways thanks for the note.
I'll make another video with some alternative local soundtrack then.
BV, Let us try your FB Video, see if it works here.
https://www.facebook.com/photo.php?v=473051982740475&set=vb.100001070323149&type=2&theater

It says: This content is currently unavailable

t_hunter44

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Re: The Science of Stream Deposition
« Reply #25 on: January 02, 2013, 04:09:08 PM »

Yes Admin,
It's about the soundtrack that i used Depeche Mode's "Gold" tune.
I have clear acknowledgement about the soundtrack, that no intentions of copyrights infringement is being meant.
The video definitely is mine, i just found it relevant to incorporate the tune "Gold" since the videos and photos talks about Gold.
Well, its sad that even with complete acknowledgement about the song, they still ban it in some countries like yours.
Maybe i'll just have a "local" someone sing the "Gold" tune to incorporate it to my videos.
anyways thanks for the note.
I'll make another video with some alternative local soundtrack then.
BV, Let us try your FB Video, see if it works here.
https://www.facebook.com/photo.php?v=473051982740475&set=vb.100001070323149&type=2&theater

It says: This content is currently unavailable

     Immediately after I posted that Link, I tried it and I was able to access the Link, however, it is now not accessible. Sorry, I tried but something is stopping us to access the Link and I do not know what it is that is preventing us to gain access. It was a good and educational Video while it lasted.

Offline Ben Valmores

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“Destiny is not a matter of chance. It is a matter of choice: It is not a thing to be waited for, it is a thing to be achieved.”
---William Jennings Bryan

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Re: The Science of Stream Deposition
« Reply #27 on: January 06, 2013, 09:08:37 AM »
http://www.firstpost.com/topic/place/philippines-the-art-of-mining-hardrocking-alluvial-mining-in-composte-video-duZiaZuN27c-782-9.html

This video contains content from The Harry Fox Agency, Inc. (HFA) and EMI, one or more of whom have blocked it in your country on copyright grounds. However, I am able to watch all the other video's listed there.
TW