black sand clean up

[digger61]

I've got some questions about this as well.....isn't cracking the black sand via salt and heat as good as going to the trouble of grinding it up? I thought about cracking my sand and then putting in an old ice cream maker along with citric acid, some ball bearings and letting it tumble for 24 hours. Would this achieve approximately the same results as crushing do you think? Going to a claim in a week or two that has a LOT of fines and flour gold in the topsoil and I don't want to let one speck get away through my black sand or anywhere else!

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[Traveller]

digger

From what I understand, salt roasting, cracking and acid soak achieve the same results as grinding. Most authorities agree that roasting will burn off pyrites bound to particles of gold (watch out for arsenic fumes from arsenopyrites) and acid will consume any iron particles binding gold particles.

The ball bearings rolling around in your ice cream maker are basically a re-invention of the ball mill. If left long enough, you will likely get the same reduction in particle size as his roller mill does and free up just as much fine gold.

What I don't understand is the concentration of citric acid to use. It can be bought in the powder form at a reasonable price. Can one make as strong a solution of acid from the powder as needed?

Regards

Bob

[likely gold]

Hi guys & gals; I'm a placer miner in the cariboo reg in B.C. Canada, I get a lot of very fine gold and have come to the conclusion the only realist way to handle my cons is to reconcentrate and then pour a dore bar. My question is, I run about 2/3 iron sulfides and 1/3 black sands,,, does anybody know what I should use for the best flux? thank you....tlt

[Mineexplorer]

Have you manage to smelt the black sand and get your gold out of them

[ohiochris]

To smelt black sand directly it needs to have a HIGH amount of visible gold in it. If not then you wont have much luck at all smelting it , just wind up with a chunk of nastly looking slag. Not all black sand will have coated gold hiding as black sand. You also have to take into consideration that you need cone molds to pour the melt into so your gold will go to and be concentrated at the bottom. You really shouldnt try to smelt any more at a time than will fit in your mold , and unless you have a lot of them , that limits your melt to just a small amount , since you need room for the melted flux too. The best thing to do is run all your concentrates over a miller table , sucking up all the visible gold you see into a snuffer bottle. When you get enough in the bottle you can smelt that , since it will be mostly visible gold with probably just a small amount of sand mixed in it. If you are careful , you will have only gold in the bottle and you can get away with just "melting" it in a melting dish with a torch. Blindly smelting black sand because you assume there is gold in it though will generally not help you any. A miller table is your best friend when it comes to getting fine gold out of your concentrates and even though you can buy them they are easy and way cheap to make.

[ForrestAdian]

I've had a lot of good results with rare earth magnets. I can get 3 to 4 times as much black sand out of my gold with them. With a little extra time I can get the gold virtually 99 percent clean, and avoid the chemicals/extra costs. If you want to try I got mine from a place called Grainger (6-7$).

[Gold Cube]

The very first thing I do is dry and classify.
Dry is always best when classification is going below 50 mesh.
When you are classifying, never go more than 2X the mesh size. I start with 8 mesh then 16, 20, 30, 50, 70, 100, 200, and 400 mesh.
Then I remove the magnetics from each size.
I get a little anal about the black sands, I store them all in their individual sizes. Someday I'll figure out why. I do have a video out there that shows my black sand removal technique. Works well with totally dry or totally under water wet, If it is just damp it is sticky and is like a claw grabbing everything. After I get all the non-magnetics out, it's time to pan.
My favorite pan style:
The pan I like best is the black 10" with the bottom 1/4" dropped straight down. The stone tap is a very sharp tap, an angled bottom to side conversion can't stop the gold from climbing. The 1/4" 90º wall at the bottom will stop it dead in it's tracks.
Then I start the panning process:
Now all you have to do is start by normal panning to minimize your material, get as much light stuff out as you can over a catch pan. I'll take care of the easy stuff first, 100 and above. Nothing special here, The Golden Rule is, if everything in your pan is the same size, gold RULES!
This is the rub your belly pat your head part.
I back wash in the pan with water moving from front-to-back not round and round. I hold the pan, as a clock at 11:30 with my left hand on top, then I put my pocket knife or a rock in my right hand for tapping.
When back washing you are looking for the water to move up both sides and collide at 12:00, just like waves on a beach. This way, if there is any gold trying to get away from the edges, the wash current will send it back and center it.
When you are ready to clean the gold, settle it all at 12:00. With the left hand, grab the pan at 11:30 and grab the rock with the right. Start the wave motion, adjust the angle until the material just starts to move.
It's kind of a rhythm now. Tap the pan at 12:30 at a rate of about 3 taps per second. At the same time keep the wave action going at a pace of 1 second per cycle, front to back. Now if you think you can keep it straight, hesitate while the water is over the material at the far end of the pan, 12:00, for 2 taps then back wash. That little hesitation will really concentrate the gold in a smiley face. As the face shows up, you can stop tapping and just wash, then tap as needed to keep control of the gold. It's the sharp tap that persuades the little stuff to climb. Panning that little stuff is a real joy, but It does take some practice.

Mike

[TyD59]

Thanks for the technique Gold Cube Mike! I l also love my Gold Cube!

I ran across your old post, and I am wondering, do you process the ferris and non-ferris material that you separated? You said after you get all the non-magnetics out, it's time to pan, but the magnet pulls the ferris particles out. I'm thinking you meant pull out the ferris particles, pan the non-ferris material? Have you found the ferris material to not contain much gold?
-TyD

[KevinInColorado]

Mike's description of finish panning is really good, I would only add that you want a smooth bottom pan for his tapping technique to work well.

@Mike - I save all of my dried, classified heavies too, am also not sure why. Maybe I should just run them back thru a Gold Cube (bigger stuff first) and then dump it all in my back garden....hmm

[soupfreak]

I also like saving all my black sands. I think the reason might be the fact that even if you don't hit any of the shiny, at least you have evidence that the technique is right.

Also, looking at it under a USB microscope is kinda cool, too.

[Goodyguy]

I observed Mike in person at a seminar in Dayton Ohio this year where he demonstrated his "Pat Your Head Rub Your Belly" style of walking the gold to the edge of the black sand in the bottom of a gold pan and I was impressed at how easily he did it.

After he showed me the correct angle to tap the pan, I now have no trouble getting the gold to immediately walk the line. I could do it before but it took way longer and never as consistent.

Thanks Again Mike,
GG~

[Ayeyou]

Running your concentrates on a Miller table should not be the end of your treatment of those cons. Attached is an assay that I had done on the tailings from my Miller table. The sample contained NO visible gold and yet assayed at 2449 grams per ton gold remaining in those " tailings". I am trying to figure out the best method of extracting these values being as we produce 1/2 ton day of the concentrate in our placer operation.



I have managed to extract gold at a value of 500 grams per ton using Mercury but obviously I am missing the most of the gold.

[Goodyguy]

To smelt black sand directly it needs to have a HIGH amount of visible gold in it. If not then you wont have much luck at all smelting it , just wind up with a chunk of nastly looking slag. Not all black sand will have coated gold hiding as black sand. You also have to take into consideration that you need cone molds to pour the melt into so your gold will go to and be concentrated at the bottom. You really shouldnt try to smelt any more at a time than will fit in your mold , and unless you have a lot of them , that limits your melt to just a small amount , since you need room for the melted flux too. The best thing to do is run all your concentrates over a miller table , sucking up all the visible gold you see into a snuffer bottle. When you get enough in the bottle you can smelt that , since it will be mostly visible gold with probably just a small amount of sand mixed in it. If you are careful , you will have only gold in the bottle and you can get away with just "melting" it in a melting dish with a torch. Blindly smelting black sand because you assume there is gold in it though will generally not help you any. A miller table is your best friend when it comes to getting fine gold out of your concentrates and even though you can buy them they are easy and way cheap to make.

I have read that......

"One way to keep from ending up with the glob of slag is by smelting the Ore to lead, then rabbeling it in zinc to recover the gold and silver then by skimming off the zinc and running it through a distillation process to remove it, thus leaving the gold and silver as a dore that could be refined."

*NOTE "the black sand must be roasted first to remove any sulfur, or the sulfur will convert the lead into lead sulfide,
and seriously mess up the process."

I have no idea what "rabbeling" is

I also found this:
http://nevada-outback-gems.com/Refer...ng_n_roast.htm


Am unable to find any commercial refiners who refine black sand concentrates. Anyone know of any?

GG~

[johnnysau]

Im sorry but the numbers posted seem OUTRAGEOUS to me. 2449 gms per ton !
I would look very carefully at the assay and its interpertation im looking at the PPM of 10 and the meaning there, which is about .291 OZS per ton
which makes sense.
Like Judge Judy says, if it sounds to good to be true, it probaly isnt.

Though as a potential prospector i hope your numbers are true, But i would be very skeptical.
johnnysau

[CptJbud]

Goodguy, could you explain what that magic correct angle is for tapping?

[Goodyguy]

Goodguy, could you explain what that magic correct angle is for tapping?

Ok but you're going to owe me .........


I had been doing it wrong by tapping straight at the edge of the pan in the direction as shown by the arrow.




The correct way is to tap the pan downward on the same angle as the sides of the pan as shown by the arrow. What a difference it makes!




GG~

[CptJbud]

Thanks Goody! When I get to be the first guy in FL to find gold, I'll draw you a map