Capt Nemo
Bronze Member
After the 3 cubic feet I took off the beach earlier, I finally ran the tailings to see what, if any, my losses were. I didn't classify these runs, so I had pea gravel in the mix. I ran 4 cleanouts, then superconcentrated, then classified for the miller table.
The Model 4
Top, wild losses. Bottom, supercon losses.
Here is what made it to the table.
What you can see is that the wild material losses were quite low, and the superconcentrating losses were quite high. The only thing that I can think of is the amount of gravel that was in the bed. All the other bed parameters were the same for the runs. During the runs, you could feel the gravel moving around in the bed, and that may be kicking the gold out of the bed. The wild run would have a lot less gravel in the bed, and correspondingly also had less loss.
Here's the gravel.
So it appears that keeping the finer gravel out of a fluid bed aids in fine gold recovery. Of same sized material, gold wins! Looks like I'll have to preclassify to window screen first to get out the pea gravel. The Gold Cube also needs windowscreen classification for Superior beach sands, and that was built for these sands. The Model 5 highbanker bed will also need more cleanouts, though it's bed is 1/2" deeper at 3" and twice as long, it will still collect gravel quickly, maybe every 6-8 buckets to keep losses to a minimum.
The Model 4
Top, wild losses. Bottom, supercon losses.
Here is what made it to the table.
What you can see is that the wild material losses were quite low, and the superconcentrating losses were quite high. The only thing that I can think of is the amount of gravel that was in the bed. All the other bed parameters were the same for the runs. During the runs, you could feel the gravel moving around in the bed, and that may be kicking the gold out of the bed. The wild run would have a lot less gravel in the bed, and correspondingly also had less loss.
Here's the gravel.
So it appears that keeping the finer gravel out of a fluid bed aids in fine gold recovery. Of same sized material, gold wins! Looks like I'll have to preclassify to window screen first to get out the pea gravel. The Gold Cube also needs windowscreen classification for Superior beach sands, and that was built for these sands. The Model 5 highbanker bed will also need more cleanouts, though it's bed is 1/2" deeper at 3" and twice as long, it will still collect gravel quickly, maybe every 6-8 buckets to keep losses to a minimum.
