I've been out to the stream for a couple of weeks now with the sluice I made. I've been taking careful notes this time around. I did more firewood cutting in that area than gold panning and am dividing my time between the two activities.
I ran a little over half a 5-gal bucket through the sluice and noted the composition of the soil including how much sand, gravel, and stone. After cleaning the sluice I got just under a tablespoon of black sand and four tiny flakes, giving me a total of 7 flakes in my specimen vial now. Last year hadn't produced the six flakes I thought, after carefully looking at them, it was only three I could be sure of. Some pyrite was in that batch, I found some nice quartz pieces with veins of pyrite in them.
I estimate that using the sluice I made with the latest improvements in design and methods I currently use, I can get better than 8 flakes per bucket. I've even calculated the volume of material needed per one hundred flakes and hope to reach a goal of 12 or more flakes per 5-gal bucket making it 8 buckets per hundred flakes. This would equal around 350 gold flakes per cubic yard of soil processed.
There are ways to speed up the process and I will be noting the time for processing each bucket load. Also, there is the issue of the finer gold particles known as flour gold. I will need special equipment to extract that from the black sand. I will be making a mini-sluice with a small pump and see if that might do the trick, otherwise I may have to buy that equipment at some point. So I'll be saving the black sand I have panned through already to reprocess it for the fine dust at another time.
ETA: It took me half an hour to dig up and screen out a 5-gal. bucket down to a 1/8" mesh then another half an hour to run the bucket through the sluice one scoop at a time, an hour-long process in total. Each scoop was screened through a kitchen sieve with a 1/16" mesh so only fine material went through the sluice. The bucket of material pretty much filled the sluice but after an hour of the stream flowing over it, it was half gone with streaks of black sand visible now. I estimate after three hours there won't be much sand left. I placed field stones in the sluice to cause more turbulence and help catch gold flakes. I'll check it tomorrow and see what is left in the sluice and then pan up the remaining sand.
The angle of the sluice is around a 3/4" drop every foot as it drops 3 1/2 inches from top to bottom (5ft). Based on the bubbles floating down it, the flow was around 1 foot per second. It may be too fast and I'll need to add legs on the end or add a foot or so to make it a little more level.
I ran a little over half a 5-gal bucket through the sluice and noted the composition of the soil including how much sand, gravel, and stone. After cleaning the sluice I got just under a tablespoon of black sand and four tiny flakes, giving me a total of 7 flakes in my specimen vial now. Last year hadn't produced the six flakes I thought, after carefully looking at them, it was only three I could be sure of. Some pyrite was in that batch, I found some nice quartz pieces with veins of pyrite in them.
I estimate that using the sluice I made with the latest improvements in design and methods I currently use, I can get better than 8 flakes per bucket. I've even calculated the volume of material needed per one hundred flakes and hope to reach a goal of 12 or more flakes per 5-gal bucket making it 8 buckets per hundred flakes. This would equal around 350 gold flakes per cubic yard of soil processed.
There are ways to speed up the process and I will be noting the time for processing each bucket load. Also, there is the issue of the finer gold particles known as flour gold. I will need special equipment to extract that from the black sand. I will be making a mini-sluice with a small pump and see if that might do the trick, otherwise I may have to buy that equipment at some point. So I'll be saving the black sand I have panned through already to reprocess it for the fine dust at another time.
ETA: It took me half an hour to dig up and screen out a 5-gal. bucket down to a 1/8" mesh then another half an hour to run the bucket through the sluice one scoop at a time, an hour-long process in total. Each scoop was screened through a kitchen sieve with a 1/16" mesh so only fine material went through the sluice. The bucket of material pretty much filled the sluice but after an hour of the stream flowing over it, it was half gone with streaks of black sand visible now. I estimate after three hours there won't be much sand left. I placed field stones in the sluice to cause more turbulence and help catch gold flakes. I'll check it tomorrow and see what is left in the sluice and then pan up the remaining sand.
The angle of the sluice is around a 3/4" drop every foot as it drops 3 1/2 inches from top to bottom (5ft). Based on the bubbles floating down it, the flow was around 1 foot per second. It may be too fast and I'll need to add legs on the end or add a foot or so to make it a little more level.
A trail goes two ways and looks different in each direction - There is no such thing as a timid woodland creature - Whatever does not kill you leaves you a survivor - Jesus is NOT a bad word - MSB