Panning For Gold: Techniques For Separating Fine Gold

Gold recovery is a common procedure for gold mining operations, but it can be a tedious task if not done efficiently. One of the simplest and oldest methods of gold recovery is panning, which involves filling a pan with a combination of loose gravel, dirt, and water and manually shaking the pan to eject lighter sediments, leaving the denser gold at the bottom of the pan. While panning is a straightforward and cost-effective method, it can be time-consuming, especially when dealing with large volumes of concentrate.

To streamline the process, miners often employ sluice boxes, which utilise a series of angled platforms and riffles to trap gold particles as water washes the ore or alluvium down the sluice. The gold-laden concentrate can then be further refined using methods such as spiral concentrators, vortex concentrators, or centrifuges, which take advantage of gold's high density and gravity to separate it from other minerals.

Other techniques, such as magnetic separation and chemical leaching, can also be used to enhance gold recovery, depending on the specific conditions and equipment available. Ultimately, the choice of gold recovery method depends on various factors, including the type of ore, particle size, and available resources.

Use a sluice box

Sluice boxes are a simple and inexpensive piece of equipment used to recover placer gold from a stream or river. The basic design has been used for hundreds of years, with many improvements since the early days. Modern designs are both lightweight and portable, making them great for the weekend prospector.

Step 1: Select a Sluice Box

There are many different sluice boxes available on the market, and they will all find gold. You can also make your own sluice box using some basic tools and materials. However, it is important to invest in a quality piece of equipment that can handle years of abuse. Cheap, poor-quality equipment is never a good idea when gold mining.

Step 2: Find a Good Location

Find a location with good potential for gold. Identify an area with a good flow of water and the possibility of gold. Remember that it is called prospecting, so be prepared to move around and sample several different areas. Gold does not distribute itself evenly throughout a stream, so you have to search for it. You may want to use your gold pan first to locate some gold before setting up your sluice box.

Step 3: Set Up the Sluice Box

Setting up the sluice box properly is crucial but can be tricky. Find a fairly shallow area with a decent volume of water. Set up your sluice box parallel to the stream flow and anchor it with several large rocks to secure it in place. Adjust the sluice box to have a slight decline in the riffles, with about 1” of drop for every foot of riffle. For example, a three-foot-long sluice box should have its downstream end about 3” lower than its upstream end.

Step 4: Regulate Water Flow

Regulate the flow of water entering the sluice box. You want enough flow so that when you shovel gravel into the top, the lighter materials will work their way over the riffles while the heavier materials, including gold, will drop out of suspension and settle into the riffles. Use rocks at the entrance of the sluice to funnel more water over the riffles and make slight adjustments to the angle. Test the setup by taking a few shovels of gravel and observing how it works its way through the sluice.

Step 5: Shovel Gravel

Once the sluice box is set up correctly, start shovelling gravel into the head end of the sluice box. It is recommended to classify the material before adding it to remove larger rocks and gravel, as they likely do not contain gold and may alter the effectiveness of the riffles. Slowly add a small scoop of gravel at a time and watch it work its way through the box. A garden trowel can help ensure you don't overload the sluice box.

Step 6: Process Concentrates

When you are ready to process the concentrates, carefully remove the rocks anchoring the sluice box and take it out of the stream. Keep the sluice box level to avoid losing any gold. Place the bottom end into your cleanup bucket and inspect the riffles for visible gold nuggets. Remove any large pieces with tweezers and place them into a vial.

Step 7: Clean the Sluice Box

Take apart the sluice box and remove the carpeting or matting used to capture the gold. Rinse it thoroughly in the bucket to ensure all fine concentrates are collected. Rinse the riffles and all parts of the sluice box until your bucket contains all the fine concentrates.

Step 8: Final Processing

At this point, you can choose to process the concentrates now or reset your sluice box and continue shovelling. Many prospectors prefer to save their concentrates and process them later at home, allowing them to maximise their time at the river. You can use a simple gold pan or an automatic panner for the final gold recovery.

Use a gold pan

Gold panning is a simple process, but it requires time and practice to perfect. Here is a detailed guide on how to use a gold pan to find gold:

Step 1: Choosing a Location

Select a spot along a river or stream where gold has previously been found. The water should be at least six inches deep and moving at a gentle pace—enough to carry away silt and debris but not so fast that it disturbs your panning motions. Look for a spot with large rocks or a fallen tree along the edge, as this will make for a more comfortable experience.

Step 2: Gathering Equipment

You will need a gold pan, which can be made of metal or plastic. Plastic pans are better for beginners as they are lighter, rust-proof, and black, making it easier to spot gold. You will also need a classifier (a sieve or strainer), a small spade or screwdriver, a pair of tweezers, a glass or plastic bottle, and a sniffer bottle (a small flexible plastic bottle with a tube attached).

Step 3: Preparing the Pan

Fill your pan about three-quarters full of gravel and submerge it just under the water's surface. Shake the pan vigorously back and forth and side to side without washing the material out. Then, switch to a gentle circular motion to wash away the lighter dirt, clay, and sand. Roll any roots or moss over the pan to capture any gold-containing dirt. Repeat this process until only large rocks and heavy concentrates like gold and sand remain.

Step 4: Washing Out Lighter Sand and Gravel

Tilt the pan slightly away from you and swirl it from side to side with a forward tossing motion, as if you were about to flip a pancake. Be cautious but use enough force to move the surface of the pan. Level the pan and shake it back and forth underwater. The gold will settle at the bottom, and the lighter material will come to the top. Repeat this process until only about two cups of heavier material remain, including black sand and hopefully gold.

Step 5: Washing Out Black Sand

Raise the pan out of the water, leaving about an inch of water in it. Tilt the pan towards you and slowly swirl the water and materials in a circle. This allows you to check for larger nuggets that can be picked out by hand. If you find any, place them in a container. Submerge the pan again and repeat the previous step, being careful not to shake too vigorously, or you may lose gold.

Step 6: Using a Magnet (for Plastic Pans)

If you're using a plastic pan, you can use a magnet to separate the gold from the black sand. Remove the pan from the water, keeping it as dry as possible. Place a magnet on the bottom side of the pan and move it in a small circular motion. Black sand is magnetic and will be attracted to the magnet, making it easy to separate from the gold.

Step 7: Final Separation

Pour the remaining black sand and gold into a bottle, preferably using a funnel to avoid spills. You can now yell 'Eureka!' and proudly call yourself a genuine gold prospector!

Tips:

• Use a classifier to size down the material before placing it in the pan. This will make it easier to separate the gold from larger rocks.
• Don't be afraid to get your hands wet and break up any clay balls or roots—they can hide gold.
• Re-shake and re-stratify the material in the pan often to keep the gold at the bottom.
• Work the material down to just a few tablespoons of black sand before looking for gold. Many novice panners stop too early with too much material left in the pan.
• Use a sniffer bottle to quickly suck up any gold you spot.
• Practice makes perfect! Panning is a skill that improves with time and muscle memory.

Use a magnet

Using a magnet to remove fine gold from a pan of concentrate involves a careful process. Here is a step-by-step guide:

Firstly, it is important to note that magnets are typically used after other methods of concentration, such as panning or sluicing, as they are effective for separating small amounts of magnetic material. When using a magnet, always ensure it is covered with a piece of paper to avoid losing any gold particles. This is a crucial step in the process.

To begin, place the dried concentrate in a pan. Use handheld magnets to carefully attract the magnetic minerals, such as magnetite, to the bottom of the pan. The magnet should be moved across the pan in a sweeping motion to ensure all magnetic particles are collected. Once complete, remove the paper from the magnet, ensuring the attracted particles are facing upwards, and gently tap the paper to discard the magnetic material.

It is important to note that gold can sometimes be found within the attracted particles. To separate the gold, methods such as roasting, tumbling, or using a stamp mill can be employed. These processes will help free the gold from any clumps of magnetic sand.

After the initial separation, it is recommended to repeat the process at least once more. Spread the final concentrates onto a clean sheet of paper and use the magnet to attract any remaining magnetic black sands. Again, carefully remove the paper from the magnet and gently tap to discard the attracted particles. This additional step ensures that any gold carried off with the magnetic sands is recovered.

Using a magnet to remove fine gold is an effective method, but it is important to be cautious and thorough to avoid losing any gold particles. The process may need to be repeated multiple times to ensure all magnetic material is removed and to maximize gold recovery.

Dry out the concentrate

Drying out the concentrate is an important step in the gold recovery process. It is especially useful in arid regions where water is scarce or in places where it is challenging to access a wet recovery system.

The process of drying out the concentrate involves removing moisture from the material to prepare it for further separation and gold recovery. Here are some detailed instructions on how to effectively dry out the concentrate:

• Set up a safe workspace: Choose a well-ventilated outdoor area or a space with adequate airflow to ensure that any vapors released during the drying process are safely dispersed. Avoid enclosed spaces to prevent the buildup of potentially harmful vapors.
• Use a metal pan: Pour the concentrates into a small metal pan, preferably a finishing pan. This type of pan is ideal for drying and heating the concentrate.
• Apply heat gradually: Place the pan containing the concentrates over an open fire or a gas stove. Heat the concentrates slowly and carefully. Avoid excessive heat as it may cause the lead present in the concentrates to melt and mix with the gold.
• Monitor the drying process: Pay close attention to the concentrates as they heat up. Ensure that the material is thoroughly dried without overheating. Be cautious to prevent boiling or bubbling, as this can cause gold to spatter out of the pan.
• Avoid indoor heating: Do not attempt to heat the concentrates indoors or in a closed environment. Always perform this step outdoors or in a well-ventilated area to ensure your safety and prevent the inhalation of potentially harmful vapors.
• Exercise caution: Heating the concentrates can release vapors, so it is important to prioritize your safety and the safety of those around you. Ensure that any vapors are carried away from you and bystanders.
• Stop heating at the right time: Discontinue heating once the concentrates are thoroughly dried. You don't want to overheat the material, as it may affect the integrity of the gold and other components.
• Allow cooling: After heating, let the concentrates cool down sufficiently so that you can handle them safely. Touch the pan to gauge the temperature, and if it is comfortable to the touch, you can proceed to the next step.
• Screen the cooled concentrates: Once the concentrates have cooled, use a piece of window screen (about 12-mesh) to separate them. This will help isolate the larger-sized particles and make the next steps more manageable.

By following these steps, you will effectively dry out the concentrate, preparing it for further separation and gold recovery. Remember to exercise caution and prioritize your safety throughout the process.

Use a gold extractor

Using a gold extractor is one of the final steps in gold recovery. It is a safe and effective way to work your gold concentrates down with no loss, leaving only about a tablespoon of black sands remaining.

To use a gold extractor, you must first ensure that you have worked your concentrates down as far as possible to remove all the black sands that you can while the material is still wet. You can do this by using a finishing pan inside a small wash tub.

The next step is to dry out your final concentrates. This can be done by pouring them into a small metal pan and heating them slowly over an open fire or gas stove. It is important to do this outside or in a well-ventilated area, as you do not want to inhale any vapours given off during this process. Be careful not to heat the concentrates too much, as this may cause any lead that is still present to melt and bind to the gold. Once the concentrates are dry, let them cool.

Once the concentrates are cool enough to handle, you can begin the separation process. Place a small piece of window screen (about 12-mesh) over a clean piece of paper. Pour the concentrates onto the screen and gently shake to separate the larger-sized pieces. Collect any gold that falls through the screen into a gold sample bottle.

The remaining concentrates can then be classified through a finer-mesh screen, such as a stainless steel tea strainer (about 20-mesh). Again, pour the concentrates onto the screen and shake to separate the larger pieces. Use a magnet to remove any magnetic impurities, and a fine paintbrush or your fingers to separate out the rest. Collect the gold in the gold sample bottle.

Finally, take the fine concentrates that passed through the final screening and spread them out over a clean sheet of paper. Use a magnet to separate the magnetic black sands from the gold. Be sure to go over the black sands with the magnet multiple times to ensure that all the gold has been removed. Once you are satisfied that all the gold has been recovered, pour the black sands into your black sand collection.

Now, you should be left with only fine gold, possibly some platinum, and a small amount of non-magnetic black sand. To separate the remaining black sand from the gold, blow lightly over the paper while vibrating it. The black sand should blow off little by little, leaving the gold behind. Once all the black sand is gone, you can pick out any remaining platinum and separate it from the gold.

Frequently asked questions