Did you know that the recovery of fine gold usually makes up for most of the gold found by small-time prospectors? It is much more abundant and is generally found in places that are easier to reach. The problem with fine gold is that its tiny and misplaced lock boxes can unintentionally let it pass. To remedy the problem, you must know the main factors involved. The speed and volume of the water are essential! Even in a poorly designed lock, if you have the volume and speed of the water set in, you will still catch gold more effectively than if you use a high-end professional lock that is poorly configured. In addition, the angle at which the lock boxes are located is also very important. The angle will affect the speed of the water as it descends, as well as how quickly the gate can clean itself. If the angle is too shallow, larger rocks and chunks of clay can settle on or around the riffles and cause turbulence in the water that will effectively kill the rear eddy action created by the riffles. That Will Make you lose gold! These points being the most critical, the next is the construction and design of your gate. Their ability to catch gold and specifically fine gold is largely decided by the riffle designs or catch mat systems.
Finding the right water flow and speed for your circumstances is absolutely essential. It can be tricky and may require you to block the flow of water from your gate inlet or introduce additional water. This can be accomplished by making a small rock dam in the stream or river bed. Depending on where you are looking, this could be considered a violation of local Fish and Game laws, so be careful with them. Most likely, if moving rocks in the creek bed is considered a violation, so is the use of a sluice box. Make sure you know the laws !!!
The more volume of water, the better, and in general, it doesn’t hurt to fill the gate with water to the top of the sides if possible. A good recommended minimum depth is about 2 inches. The volume is generally separate from the speed of the water, so you can easily adjust it by lowering the gate further into the water or by finding points deep in the stream bed that act as a funnel for your gate.
Proper flow can be judged using small pebbles or a handful of sand. Drop it at the entrance to your lock and watch it flow. All but the heaviest particles should be washed off within 3 to 5 seconds, depending on the length of the airlock. 3 is a bit fast, but will allow for much faster production of concentrates at the cost of losing some fine gold. 5 is a bit long or almost correct depending on the roughness of the material you are applying. You should be catching a lot of fine gold at that speed, but at the risk of larger rocks getting caught in the rifles and disrupting the flow. However, you can adjust the angles to fix that.
When installing a lock, the proper angle must be observed. It is generally 5-7 degrees sloped and should allow most round rocks and pebbles to pass through easily. You don’t want the material to slide, but rather to slide slowly. An ideal speed is for a larger rock to clean itself in 3 to 5 seconds in a medium-size sluice box. Also remember that the angle affects the speed of the water as it travels through the lock. Also, it is sometimes impossible to achieve right angles if the stream is very flat. In such a circumstance, you may be asked to create a makeshift dam with more rocks to raise the water level on one side so that you can feed it through your lock. But that can be a lot of work, and it’s usually best to try increasing the speed of the water.
With the right angle, water flow and speed, now is the time to use our lock boxes! Many people pre-check their material before putting it through the gate. It’s a lot of work and a properly configured gate doesn’t need this. However, with that said, if you don’t shortlist or rate the material, you will probably lose Some fine gold. This problem can be solved by using a sorting screen over the gate inlet as the soil moves in. I used an old dishwasher rack that I found on the creek bed and put it in the entrance to my lock box. the water got through it and when I dump material it will wash it off leaving the bigger rocks and chunks of clay so you can easily throw them away. It’s a great lightweight solution that really speeds up my production. It is also a much better alternative to dry screening the material directly at the excavation site and then bringing it over 10 feet to my lock. Results can vary, but at this point you should have a pretty good intuition about the possibility of losing gold.
Removing the lock from the stream can be a complicated process and will inevitably lead to the loss of some gold. It is strongly recommended that as you remove the airlock from the water jet, you put a bucket or saucepan at the end to catch any accidental drops. I have seen unsuccessful attempts to remove a lock that cause small pieces of gold to wash back into the stream. Be very careful.
After that cleaning is a breeze and not to mention fun. You can finally see how all your hard work paid off. However, it’s worth noting that if you have one of the next-gen plastic gates, you often have the added benefit of even easier cleaning, as well as a good view of what’s being collected during the unloading process. The disadvantage is the lower production capacity.
Hopefully that should get any new prospector started! Hope you enjoyed my guide!