Dredging For Gold
Gold dredges enable one or two people to move an extraordinary amount of material in a day. Dredges will suck off all the low gold bearing material quickly while still recovering a high percentage of the fine gold scattered through it. Then once you are down to the hard rock bottom a dredge has the ability to suck it clean like a vacuum cleaner. Attention should always be paid to the fine cracks and crevices in the bedrock as the gold works its way down into them and will often have to be prized out before it can be sucked up.
Choosing the right dredge for you is one of the most difficult parts about dredging for gold. There are numerous styles of dredge and sluice components. And you can get them in any size your budget and mining license will allow. Generally speaking the bigger the dredge the more material you can move in a day, but also the higher your outlay and running costs will be.
The difference between a four inch dredge and a six inch dredge (they are measured by the size of the intake pipes) is not 50% more productivity. As you gain an inch in size the proportion of work achievable goes up on an exponential scale. Bigger intakes will suck up and spit out bigger rocks, so that means you will have less material to manually pull away from the front of the dredge. Also, the bigger capacity on the motor and pump the deeper you can operate and still suck the material up the pipe. Some dredges operate with a submersible sluice unit which enable you to go deeper with a smaller unit. However, these dredges are more cumbersome to use and are not as efficient at gold recovery with most of the fine gold flowing straight back into the river.
You will also need to consider the water flow available if you are working a small stream. A large floating dredge requires a good amount of water to keep it mobile and to keep a consistent flow of water in the nozzle. If the dredge is sucking air it can damage the pumps but it also has a tendency to dislodge the gold from the riffles.
Do not get bogged down in the statistics of all the dredges, but do make an effort to do some study before you buy your dredge and you will be more likely to be happy with the final result.
Check our Classified Listings for second hand dredges and mining equipment.
Once you have harvested your gold and concentrates with the dredge you will want to maximize your gold recovery.