Gold Dredging
Underwater suction gold dredges have been around for quite some time, and have been used with varying degrees of success so there really is nothing new when referring them. Yet on the other hand, time will generate many improvements as is the case of what happens with all equipment. The rate of recovery being poor and also weight are the most important drawbacks of most dredges. All of these, on the other hand, give the impression of being acknowledged by the recreational miner as the most outstanding tool available which will facilitate the recovery of the gold from superficial creeks, rivers, or locations that were literally impossible to work in the gold rushes of times past. Cracks in bedrock which are underwater are just about impossible to clean by any other method. The surface type of gold dredge is supposed to be able to produce a practical recovery rate of fine gold and they are also easily portable. Bear in mind that the underwater models are hardly ever used any more. Portability appears to be the key to success. a large amount of prospecting and moving from spot to spot until the color is obtained in the sluice box is at all times essential. 
There have been claims of 90 % to 100 % recovery of fine gold which are made by quite a few dredge manufacturers. This is literally impossible. A quantity of fine gold has a certain quantity of natural oil which is made from the roots of grass, weeds and polluted water, and will basically float right on through whichever kind of sluice box, particularly in a surface suction dredge that is producing the large quantity of water which is necessary to obtain a suction power sufficient enough to lift the weightier gold from the bedrock. A statement which is more reasonable would be to say that the dredge has an excellent recovery rate. The recovery rate of a surface suction dredge is quite dependent on the expertise of the operator who is running it.
A lot of care must be taken to follow the advice of the manufacture with regard to the pitch or the positioning of the sluice box. If the sluice box is slanted excessively steeply and the fast water is creating a boil, this will definitely be your principal sluice robber. You must continue adjusting the tilt or slope at all times until you attain the appropriate positioning of the sluice box. At what time the header box is maintained completely full of water at the same time as operating, the rocks and the gravel will have enough time to work their way down to the bottom, giving the gold the chance to become trapped in the riffles. A similar method of determining the appropriate sluice box pitch will be reasonably applicable to whichever type of surface suction dredge. The widespread fear of all the people who are beginners at the moment that gold is not recovered straight away is that the sluice box is losing it. Ninety-nine percent of the time this is wrong; the spot just doesn't contain any gold. You ought to practice in areas where gold has been found at some point or another and learn to keep away from this common mistake. Bear in mind that the suction dredge which is of the surface type is in no way better than the operator.
Portability is just about as essential as the recovery rate. The weight of any surface type portable dredge appears to take the thrill out of recreational mining practically before you even get started. Probably 99 % of the new weekend prospectors are doing this for recreational purposes and for the chance to make a few additional dollars. Some do quite well and recovery of from a few pennyweights of gold to an ounce or so is not a rare situation. On the other hand, recreation and enjoying the wonderful outdoors appear to be the principal objectives. It will not be that much fun or recreational if you have got to pack unnecessary weight all day. The majority of the manufacturers bear this in mind and they do the effort of trying to design equipment as light in weight as they possibly can. Backpacker models which are constructed of plastic weigh an average of thirty pounds. Even a very lightweight model appears to get heavier in the evening than it was in the morning! You must choose the size of your dredge cautiously, keeping in mind that if you are not a professional and do not have a permanent claim location to work on, you will in all probability be moving and prospecting around quite a bit. There are also the larger dredge sizes which are up to four inches, these are quite common and many of them are in use, but the lightweight two-inch size appears to be the most popular and practical one of all.
