A highbanker is basically a sluice box with mobility and added height. It is mounted on a 4-legged stand that gives the sluice box the correct slope. Instead of being put right in the creek like a sluice, an engine with a water pump and some hoses transports the water up from the stream into the highbanker. Highbankers are also called power sluices. It is a self-contained unit with many uses— prospecting, sampling, and concentrate clean up.
In general, a highbanker or power sluice is extremely efficient at trapping gold. The biggest benefit of having this piece of gold prospecting equipment is the ability to process gold-bearing gravels located a distance away from a water source— in other words, you get to bring the water to the gravel, not the gravel to the water! You can purchase a highbanker with a pump/motor and all hoses and fittings included, or you can buy those items separately.
To run a highbanker, you need a system to pump water to it. Highbanker pumps can be either electric (12 volt battery) or gas driven. Some highbankers are also designed and constructed to re-circulate water so they can be employed in situations where little water is available. Keep in mind that the pumps deliver less water as your equipment location is moved uphill. Pumping uphill increases the resistance on the pump, and as you move uphill, eventually there is a point where the pump will not provide sufficient water to run the high banker. The slope on the highbanker usually ranges from about three to four inches per foot.
Next, shovel gravel into the hopper, which is mounted at the top end of the sluice box. Inside the hopper is a "grizzly" which is a series of sloping rods that filter out larger rocks. Also in the hopper are spray bars that shoot water onto the gravel that is being shoveled into the hopper. In addition to the ability to go just about anywhere, the highbanker is able to run more material in less time than a regular sluice.
Any experienced gold miner will tell you that the secret to recovering the most gold is to process a lot of material quickly— and a highbanker does just that!
Another article about highbanking for gold found here.