gold sluice riffle spacing

64 GMJVol. 17, No. 1, June, 2017 Effect of Riffle Height and Spacing of a Sluice Board on Placer Gold Recovery* 1George Agyei and 1J. Gordon 1University of Mines and Technology, P.O. Box 237, Tarkwa, Ghana Agyei, G., and J. Gordon. (2 017), "Effect of Riffle Height and Spacing of a Sluice Board on Placer gold

I had no intention of taking this sluice into the field. It worked pretty well, but it still had issues. Most of the pay dirt I run through the sluice is crushed ore from a hard rock gold mine. The gold is big and chunky. The sluice did a real good job of capturing almost all that gold. Most of the gold never made it past the first riffle or two.

Sluice-boxes are always set at an inclination, the slope of which is again a balance between conflicting factors, similar to those that determine width. A number of types of riffles have been used and includes, longitudinal riffles, blankets, mercury traps, "hungarian" or "dredge" riffles and expanded metal.

D.I.Y.- Sluice boxes/Riffle trays: These D.I.Y. Sluice boxes are DURABLE & LONG LASTING! Perfect for the person wanting to build. their own personalized recovery system for their specific recovery needs. With either 4" or 5" tall sides, they are well suited for an over/under type, 2 or 3 stage sluice for. your Dredge, Highbanker, Power sluice ...

Keene Super Sluice Box. $329.95. Riffle designed Keene Super Sluice Box for high volume separation of unclassified material from fine gold. Expanded into High bankers & more. SKU: A52S. Call now to order (855) 721-7699. If you have ever watched a program such as Gold Rush, then you will have heard about sluice boxes.

The Gold Well Vortex Drop Riffle Sluice works by creating a gentle, vertically oriented vortex. This vortex keeps material in the spiral shaped Wells in motion, causing light material to be flushed out easily and concentrating heavy material. When a piece of gold crosses this vortex, it finds no stable bed to rest on and like a heavy object ...

Gold recovery was also affected by riffles spacing. For the indicated speeds and the riffle heights the necessary spacing should not be more than 20 cm. The peak recovery was obtained at a riffle height of 1.0 cm but dropped after 20.0 cm spacing. Keywords: Sluice Board, Riffle Height, Gold, Rifle Spacing

Riffles can be made from half inch square dowel nailed about every 6 inches down the length of the sluice. The section without riffles in the top of the box about a foot long is often left for the spot where material shoveled in. This type of sluice box does catch gold, and is easy to build, but is hard to clean out at the end of the day.

The prospector's portable gold sluice box has an advantage that it can be quickly taken up and moved to a new location, as the prospector searches for spot with good gold. The grade slope when the sluice is set up usually ranges from about one to 2 inches per foot. The riffles are really the most important part because they are the part of the ...

The riffles, or gold traps in the sluice box are best described as "Hungarian Riffles". This type of riffle has proven to be the most efficient gold recovery system. As material flows over the riffles a eddy current is formed between each riffle opening.

The design and style of the riffle system is very important, for if the riffles are spaced to close or to far away from each other this can and will effect the performance of the riffles to capture gold. Also the size and shape of the riffles are just as important as the spacing is. I have never bought a sluice box, all of my boxes are homemade ...

Slope of a sluice is generally in the range of 1.3 cm (1/2 in.) to 3.8 cm (1-1/2 in.) per 30.5 cm (1 ft), depending on the size rock in the feed. To move the larger rocks down the sluice requires a steeper slope or more water, both of which cause greater gold losses. Any number of types of collectors can.

A sluice box operated for extended periods with no new material being fed to it has an increased chance of losing some of its fine gold values. How much gold loss will depend on a multitude of factors, such as the type of riffle design, how much water flow, the type and weight of concentrates and the size and purity (specific gravity) of the gold.

sluicing at approximately 1.0 cm riffle height. The lowest recovery was recorded at 0.5 cm riffle height. Gold recovery was also affected by riffles spacing. For the indicated speeds and the riffle heights the necessary spacing should not be more than 20 cm.

Most recovery systems on suction dredges use fixed riffles to trap gold out of lighter streambed materials as they are washed through a sluice box by a flow of water. Riffles are baffle-like obstructions, fixed in place along the bottom of the sluice box. They are designed and positioned so that there is a back-pressure created that sucks water and material behind the riffles from …

Our recovery trays (sluice boxes) utilize a combination of Hungarian forward riffles for coarse gold and dovetail riffles in the back section for fine gold. We currently build seven sizes of dovetail riffles and mount them with progressive spacing and various depth settings to achieve the most efficient recovery action.

The flared riffle design causes the water flow to slow as it passes through the sluice, resulting in optimum gold recovery. In working this box, water should run through very rapidly, about 2" deep, which keeps the riffles clean and will leave the gold and very little concentrates behind.

I'm not going to go into riffle design here, but know that the riffle is the key. Some riffle's like fast water and some like slow. Makes no difference here. To set up the box you have to move all the large stuff off and then get rid of most of the heavier sands. A box is running right when you fill the front with gravel (and hopefully some gold).

Riffles (gold-catching obstructions) are placed along the bottom of the sluice. Because gold is about five times heavier than the average sand and gravel in a streambed, even the smallest particles of gold will fall down between the riffles and become trapped, while the lighter material washes through with the flowing water.

Diy Sluice Box Riffles. October 20, 2021. Take a small plank of wood and use a dremel tool to carve out the riffles and other textures you want on the sluice. The 'perfect' height for 1/4" gravels would be 5/8" but this riffle height would be a custom fabrication. Homemade Backpacking Highbanker (drop riffle) Riffle.

Diy sluice box riffles. It is a simple, yet effective, tool which allows the operator to process a great deal more material than would ever be possible by simply using a gold pan. Your dredge, highbanker, power sluice, trommel or hand sluice. Alternatively the box is divided into two sections, one with and one without riffles.

Getting the feed flow, angle, spacing and the height of the riffles including the slope of the 'box were all very critical for good recovery and clearance (riffles not loading up). The riffles with a backward slope of aprox 15 degrees was about the best so far with a …

GPAA Founder George "Buzzard" Massie and son Tom explain the riffles of a sluice box used for finding gold in a creek.https://gpaastore.com/pages/gold-giveaw...

Super Wide High Banker Drop Riffle Gold Sluice. $349.00. ADD TO CART CHECKOUT NOW. Super Wide High Banker Drop Riffle Gold Sluice. $349.00. ADD TO CART CHECKOUT NOW. Successfully Added to your Shopping Cart. ... Website by Web Design Just For You ...

The ASR Outdoor Gold Panning 32-inch Portable Gold Sluice Box is a gravity fed high recovery gold prospecting and mineral collection tool. Extremely portable with an adjustable shoulder strap allowing you to take it to the mouth of the river, high into the mountains, near the base of a waterfall or anywhere in between.

Most gold sluice boxes are made out of lightweight metal and contain a removable riffle tray. The sluice box riffle tray sits on top of a carpet that traps the fine pieces of gold. When the time comes to clean out your sluice box and collect the gold, you pull out the riffle tray and wash the carpet out inside your bucket.

The riffles are the most critical part of any sluice box design, because they are what actually captures and retains the gold. For easy cleanup, you want the riffles to be easily removed, so that the heavy concentrates can be cleaned out of the …

Sometimes very fine gold particles might escape the riffles. Due to this, many sluice boxes are equipped with some type of matting or carpet that is design to capture the gold as it slides along its surface. One common type of matting is the so-called " Miner's moss". It consists of woven fibers and as its name suggests, it resembles ...

I've been mining with sluice boxes since the 1980s, so to me a sluice box is definitely an old friend. The new twist is that fluid bed sluices do not use a set of riffles and matting to capture gold like a typical sluice. Instead, they use a fluid bed of sand and small pebbles in a collection box that is cast into the sluice to trap gold.

This helps to determine where the gold values may be the most plentiful. Remember, don't overload your riffles! STEP 4: TENDING THE SLUICE After dumping each load of gravel into the sluice box, check the riffle section for large waste rocks that may be lodged in the sluice. Flick these rocks out of the riffles with your fingers.

The sluice should slope 4 to 18 inches per 12 feet, usually 1-1/8 to 1 -¾ inches per foot, depending on the amount of available water, the size of material processing, and the size of the gold particles. The riffles in a sluice retard material flowing in the water, which forms the sand bed that traps heavy particles and creates turbulence.

Some research reports done on sluice operations recommend slick plates in front of the riffles. This is to allow the gold to settle and be riding along the bottom of the sluice when it hits the riffles. This is the optimum point where one would want to have the gold located when it enters the riffle area.

Most sluice boxes use riffles or obstructions blocking free flow of gravel and sand from being washed out of the sluice box. These restrictions form low pressure pockets behind which gold will accumulate. Gold is 19 times heavier than water and …

A sluice box is one of the oldest simple machines used by gold prospectors. This is a photo of two classifying screens that i built to fit inside a rocker box. For fine gold recovery the use of riffles can actually be a negative design element and most boxes specifically built for this type of gold don't use any type of riffle system.

The recommended spacing between riffles is twice the height. Measure from the top of the leading edge of the riffle down to the sluice and double that measurement as the spacing between riffles. That 2:1 ratio is the formula for creating the proper vortex between riffles. (provided the angle of the sluice and the flow are adjusted accordingly)