My tests so far have it as efficient as an experienced panner with much higher volumes of production. It is simple to use and relatively foolproof. One of my test subjects even spun the screen pan backwards and it still worked (this guy thinks instructions are for dummies.) Another valuable place for this unit is in low water areas. Because you work in a five gallon bucket it is a simple matter to put the whole works in a shallow plastic tub and catch the overflow. The unit doesn't care if the water is dirty so you can keep re-using the water. Ten gallons of water should be enough for a good days work. You will lose some water to the waste material that you dump and that water must be made up. I also find it handy to be able to scoop some water into the five gallon bucket if any agitation has lowered the water level too much.

This will open the doors to some desert areas as well as areas far out in the boonies where equipment has to be kept to a minimum. This system does everything a concentrator should do. It classifies material by screening and it concentrates material through a constant exchange of lightweight material for heavies. Depending on your location you could process between 2 and 20 screen pans of material before clean up. Your major concern will be loading the concentrate pan with too much black sand making it hard to save fine gold. You will be able to make that determination quickly as a clean out of the concentrate pan will reveal how you are doing. It is so quick that the time spent doing a few experiments to determine how long you can go between clean outs is well worth it. Less time spent cleaning out means more time processing raw material with the resultant higher profits. I have done some preliminary work on gemstone recovery. Diamonds are of interest here but the costs to process material make it tough to take larger field samples. The ROTAPAN seems to be a suitable field concentrator as long as the operator keeps in mind that diamonds or other gemstones are much lighter than gold. This will mean less aggressive operation and more frequent clean outs. By the way - making a dirty concentrate for the first run is not a bad thing as the operator can reprocess the rough con to produce a higher grade product. Since everything can be self contained there is no chance of loss. As an experiment I ran a sample of black sand laced with fine gold. Generally recoveries with anything to do with panning are pitiful. It's not that panning won't recover the gold its just that it takes forever to process even a small amount of black sand. The ROTAPAN did very well in making a super concentrate that was much more fun to work with as the gold was so much more evident. There were gold losses but the self contained system didn't lose it for good - just misplaced it. I got into the habit of using the machine like a vibrating table in that reconcentrating the rough concentrate produced a high grade con and the discard which contained some gold was either reprocessed to produce a middling fraction right then and there or I saved the discard from the re-run of the rough con to be added to the next run. If you use the ROTAPAN as a field test unit you know that it is important to be sure the equipment you use is absolutely clean, so following samples are not contaminated. The ROTAPAN is easy to clean between samples with very little chance to have material hang up.

In gold and gemstone prospecting there is a certain niche that just seems to cause trouble. This is that leap from the basic gold pan to the sluice-box or other large volume concentrator. We have mini-sluices, we have mini-rockers, we have spiral concentrators and several things between but each suffers from some sort of problem that keeps them sitting in the storage. A twelve volt battery needed to run the concentrator and/or it's pump can start to wear a body down as it is dragged through the bush. Many of the concentrators are not much faster than a regular gold pan so there is little need to have them except as cleaning tools. And last but surely not least is the classification of "lightweight" equipment is made but when I read "A portable unit weighing ONLY 70 pounds" I have to ask myself if the manufacturer has packed their own equipment further than the parking lot. Don't get me wrong, there is a lot of great equipment out there that is portable, (in that it can be picked up and physically moved with a fork lift) but when I use the words portable and lightweight in the same sentence, I want something that weighs less than 20 pounds - less if possible. I'm dreading right? Well maybe not.

In actual operation the process would go like this,

1. Fill the five gallon pail with water.
2. Put the concentrate pan into the pail. It will hang on the rim and be suspended under the water.
3. Place the screen pan onto the post. You will find that it will spin freely on the post.
4. Fill the screen pan 1/2 full of raw gravel.
5. Oscillate the screen pan by spinning it back and forth in short arcs. This will begin the screening process and feed fine material to the concentrate pan. After a few oscillations, the screen pan is lifted so the post is just barely into the screen pan.
6. Oscillate the pan while lowering it back down the post.
7. Repeat the lift-oscillate while lowering steps one more time. This lifting action sucks fine material through the screen and down the cone to the eye of the pan.
8. With the screen pan in its fully lowered position rotate it CLOCKWISE in a full circle three or four times to let the scraper throw the waste into the bucket.
9. Take off the screen pan and inspect the oversize before tossing it away.
10. Repeat those steps until you have loaded the concentrate pan. This will vary depending on the material being run and we will discuss this further.
11. Pull off the screen pan and carefully lift out the concentrate pan keeping it level. Wash the concentrated material into a gold pan for separation.