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geowizard
09-06-2012, 07:19 AM
I recently learned of a secret weapon for capturing gold...

Gunny Sacks! The family of one miner I know, has used burlap mat in their sluices for several generations.

http://www.onlinefabricstore.net/landscape-and-garden/bags-and-sacks/burlap-bags-and-sacks.htm&utm_source=adcenter&utm_medium=cpc&utm_term=gunny%20sack&utm_campaign=Burlap%20Products

Gunny sacks are useful too for carrying those odd shaped things and for rock sample bags. I can't tell you how many times my dad handed me a gunny sack with rock samples and said; "Here, throw that in the pickup." :)

- Geowizard

goldmann
09-06-2012, 10:42 PM
Thanks for that, I got burlap sacks(to use under his angled and armor weave riffles) from Bob Dahlkle in 1991 when I got a dredge off of him. I never did use the burlap as a mat because I replaced it with something else. So I do not now how a burlap mat would work?

Greg in BC
09-06-2012, 10:50 PM
In 1980 my first mining equip was built from old BC gov't prospecting book plans and called for burlap matting. I took a number of layers and had my mother sew them together. I wanted them sewn across the top so they would be easy to clean out but she went to work and quilted them together. Looked very professional but I never told her how hard it was to get the sand out of the mat! Good thing with burlap is you can burn it when it is worn out and pan the remains - just make sure to do it outside and stay upwind in case there is any mercury in there as well. Too early in my experience to know if it was better or worse than the new mats but definitly an economic option that may need a fresh look.

Bill Bohan
09-09-2012, 09:35 AM
I am also considering burlap or a wool blanket. My miners moss and astroturff don't seem to stop fine migration between the metal box floor and astroturff inter face. I also have been considering extending my box with rough cut wood.

Reno Chris
09-09-2012, 11:06 AM
Burlap and wool are old school. Wool especially is very old school - it was used by the ancients.

Careful what you use guys - these things have been replaced for a reason. Miners moss cleans out about 10 times easier than burlap and especially wool which tends to trap and HOLD fine gold (permanently). You may have to dry and burn these things then pan the ashes to get the fine gold out of them.

Its a false economy to save $50 by using burlap over miners moss - with gold at $1740 an ounce, it makes sense to get the very best stuff on the market.

Bill Bohan
09-09-2012, 11:45 AM
The 10x easier is what concerns me. Easier to clean may mean easier to lose. I am just thinking that there might be a chelation to natural fibers that is not there with plasitcs and metal. Almost even ready to pull my stainless steel riffles out and find riffles that rust.

Reno Chris
09-09-2012, 12:44 PM
I am just thinking that there might be a chelation to natural fibers that is not there with plastics and metal.

Why would you think that? I've not heard of burlap or wool doing that.

If you want rust, ungalvanized black steel sheet isn't hard to acquire. Replace the sluice trough and the riffles with black steel and you'll really get some rust going. At the end of a week's run, you might need a whole day to chisel it all out and and a crusher to crush the solidified material. I had a friend who one season put his wet black sands in a steel coffee can at the end of each dredging day. He took out the pickers, but dumped the black sand and fines in the can for later processing. At the end of the season he had several coffee cans full of material that was rusted into a solid rock. It would have been a lot of hard work to extract those fines, so he just tossed them. After that he dried the sand out before he put it in the can.

overtheedge
09-10-2012, 07:21 AM
Back in the early to mid 70's, I used burlap gunny sack material for my sluice. The only info I could find was in old Bureau of Mines circulars and a book by Bradford Angier at the public library.

It had low bedding capacity but it holds the gold and lights. That is the problem.

Even after drying the burlap, you had to beat the gold out like beating a rug. I stuck it in a bucket and worked it over with a stick. What a hassle. In the end, I had to burn the burlap to get the remainder out. Not that there was that much, but you could beat it over and over again and still get more out.

Don't try wool because it doesn't burn for squat. Been there, done that using a military surplus wool blanket. Same problem with it not letting go of the gold.

Either might work if the gold is round and smooth. But rough gold just won't let go of the fibers.

I would use burlap only if there was nothing else available.
eric

geowizard
09-10-2012, 07:51 AM
I thought I would NEVER hear anyone complain about matting "hanging on to the gold".

Never had a problem with matting hanging on to gold. If it does that, put it back in and keep working. Pull it when it's saturated with a nice visible layer of gold. :)

JMHO...

- Geowizard

Minermike
09-11-2012, 11:32 PM
I used some car matting , that was made in the U.K. great stuff ! It had 1/4 by 1/4 inch holes all over it, about 1/4 deep but did not go through. I cut it to fit all down my sluice box. With the riffles on top. I found on a day by day basis that I only had to clean the first mat. To clean it , I bent it into a 20 lt. bucket and washed it with water. All the fine gold fell out. At the top end I did have some thin punched plate on top of the matting. I found that the gold worked it's way through the punched holes and into the matting. I did use some felt to start with but soon gave it away.

Minermike
09-11-2012, 11:45 PM
I did check all the other mats , after a long weekend or week. But I was hard pressed to find a spec of gold.

tenderfootminer
09-12-2012, 12:30 PM
unbacked miners moss will most certanly let fines migrate under it! I use a "fleece" style blanket under it and it cleans out good.as for burlap it works but does eventually need burned. My cleanups gained several oz. of fines by doing nothing other than putting a blanket under my moss...ws