- Mar 10, 2007
- Detector(s) used
- Whites TM 808, Whites GMT, Tesoro Lobo Super Traq, Fisher Gold Bug 2, Suction Dredges, Trommels, Gold Vacs, High Bankers, Fluid bed Gold Traps, Rock Crushers, Sluices, Dry Washers, Miller Tables, Rp4
- Primary Interest:
- All Treasure Hunting
I was trying to keep it in context for the OP with a backpack sluice with what I assume are low hungarians, I understand the use of Nomad scraper mats in commercial setups but you cannot actually compare small prospecting apparatus with commercial wash plants.
You are absolutely right!
We small scale miners want to capture every single speck of gold that our equipment is capable of, and will go to great lengths to accomplish that goal.
Cutting my teeth on the fine glacial gold that Indiana is known for and the fact that the paystreaks are few and far between, fine tuning your equipment to try to catch every speck was an absolute must. Most importantly choosing the right equipment for that task was critical.
After a short time of trial and error it became evident that the sluices made for general use were not set up properly for optimum fine gold recovery.
First of all the riffles that came with them were not allowing some of the fine gold to drop out of suspension due to the angle and flow required to keep the sluice from building up material.
Didn't take long to realize that the riffles had to go in order to get more of the fine gold to drop out of suspension. At the time it was found that just running carpet underneath expanded metal was the best solution. Of course classifying the material first before running was key in eliminating losses as its easier to capture gold when the particles being run are closer to the size of the gold being recovered.
What was being observed was that larger gravels would tend to send a percentage of the fine gold back up into the flow as some of the fine gold would get knocked loose by the larger gravels bouncing down the sluice. So classifying was a must.
It was also observed that a rock laying still in the sluice would speed up the flow around it causing gold next to it to release it's grip and be sent back into the flow.
Once the no riffle, no mat, self classifying fluid bed goldtraps came onto the market the fine gold losses were reduced to the bare minimum.
Then the Gold Cube with the stratifying slick plate followed by a gate trap followed by the vortex mat pretty much sealed the deal that riffles are old school as far as fine gold recovery was concerned even though pre-classifying was mandatory.
Nowadays mat improvements have completely changed the recovery rates that can be achieved in sluices with their precision riffles and alternating capture zones built into the mat completely eliminating the need for expanded metal, riffle trays, carpet, or miners moss. Of course there are those old school die hards that will never accept the change.
Riffles are common where commercial ops are concerned along with the miners moss but as you know those guys are running many tons of material and any of us would love to have the gold lost daily (10-15%+) by any of those huge wash plants.
It would not surprise me to see most of the large commercial ops eventually switch over to mats only, as the improved multi capture zone mats become more mainstream. I know that Gold Hog already has a few commercial ops using them.