They won't answer. They don't know how to run the online part of their business. Best advice, get a gold buddy!

my experience is that 'dry' washing was typically about a 75% catch rate process - if your looking for higher rates then your recirculating wet methods were closer to 99 according to the specific systems used - if your in dry areas, the problem comes in transportation of water to the field environments in question, profile, footprint ...is the media sticky or dry, loose or firm ...is your subject fine or large ...even in the mini or small footprint systems, you create them to the scope of the process - using a high backing tray, a trommel, or pre-classification methods ...cube or sluice ...each has their advantages and disadvantages according to conditions - and 'tuning' to the amount of material your wanting to run is also a major factor - this is why i 'always' spread and detect/sample other peoples tailings when i find them // in all reality, not to make excuses for Pat, but some of your questions don't have simple answers unless one knows the media and methodologies being deployed (and it becomes a question of tuning according to changing conditions day by day)

Jim Strait in his book said he built a 12"×12" wooden box to measure the amount of gold per cubic yard of material he was working. I did the calculations and built a wooden box equal to 1/2 cubic foot. So when we go from location to location we can see how much gold we have per cubic yard of material. and where we want our cut off to be...say 1 gram per cubic yard or more if we can find it. I'm sure by now you figured out how to maximize your capture rate... box angle, air speed, air volume. Use a second cloth layer in the bottom end of the box to slow the air flow and try to catch the fine gold in the bottom half/quarter of the box. I will be using neodymium magnets in the top end of my box to catch the black sand and use the magnets and the caught black sand to catch the fine gold. Same in my sluice boxes. The Gold Magic auto wet/dry panner with the motor or hand crank or both can be set up ahead of the drywasher to find the gold. I also have a Whites Goldmaster E Series with 14" coils and stock coil to hunt for black sand (and gold) and a newer garrett goldmaster 24K to hunt for black sand... any detector that gives a VDI for the ground balance point may work. Indicates mineralization type, but not amount. The newer Deus II Has both the mineral phase and mineral strength like the Goldmaster. A magnet on a stick works also to search for black sand. Set up to catch the black sand and use it to catch the fine gold. We are looking for the size distribution of the gold for the area we are working. To make an adjustment in the top box screen size.

You have to clear the material... in front of the riffle box by hand. It sounds like the angle is to steep or your feed rate is to fast or the air pressure is to high and its blowing everything up out of the riffle tray even at the gate open half way, so open it some more and maybe add more black diffuser layer in the bottom 1/4...bottom 1/2 of the tray. If you got gold running out of the box... thats good because that means you have gold... now the question is what size is it and how much is there per cubic yard. How mutch an hour can you make doing pick and shovel work. At some point the gold can be so small that their is no mechanical device made that can seperate it from its host deposition and heap leaching is all we can do. The Carlin Trend in Nevada I'd an example of microscopic gold production. Owned by Barrick and Newmont. Oil and gas is are lighter than water so they move up in the subsurface until they trap. Gold is heavier than water (19 times so it and it's associated mineral black sand mover down in the subsurface until they trap. Clay or shale or some other non permeable strata is the trap we are looking for. Preferably at the base of a hill or mountain or who knows at the base of some gravel bed. I look for microscopic quartz by picking up a handfull of dirt and dropping it and then looking at my hand in the sun. I also have a 360 power gem microscope so I can see into the world of fine gold dust missed by the weekenders. I started looking for gold with a whites metal detector and a Keene highbanker dredge combo in Wyoming in 1985. The gold was microscopic and it was the hand held pocket Panasonic 60 power microscope that got us on the gold. Then later ICP assays started to put us on the gold.

Bob Sullivan did you watch the video? I’m pretty sure their selling the new Keene 140 S dry washer.