Separating gold flakes and dust from black sand

[jetro30087]

Recently I came across some black sand deposits which appear to be rich in gold dust and flakes. I am new to refining and looking for the most effective way to separate the gold from the black sands. A large amount of it is magnetite so I should be able to extract that part using magnets, but I am uncertain how to proceed with the remaining hematite in the mixture. Since the overall amount I have is fairly small, I'd prefer to find a chemical method since I figure it would allow me to extract the most gold possible from the mixture. But I'm willing to try any methods that are economical.

 

[FrugalRefiner]

If you can see the gold dust and flakes, panning would be the most economical method for a small amount.

Dave

 

[sugianto]

We have more black sand with small gold dust that is very difficult to separate by panning.

 

[Platdigger]

"Clean gold"

 

[Finn from Ecuador]

"Clean gold"

I am not quite sure what Platdigger means but if he refers to product of this name, i would like to add that it's basically a miller table with piece of magnetic conveyor belt under its deck. By separating magnetics that way, one will lose gold with them too. As far as understand, the name of this product is targeted to undeveloped countries where the idea of clean gold means mercury free gold, not gangue free gold.

Salud

Finn

 

[Platdigger]

Not really. It works by loading up with magnetite and iron forming like little riffles. The little gold particles get embedded in the magnetite. You keep running until it fairly loads up with gold. It will catch some really small gold. I met with the inventer "patent holder" and saw him futher concentrate and do a clean up. Not saying I can do it, but I saw it done.

I think you are right about the name referring to "mercury free" gold, or at least to not using mercury for recovery. Just never thought about it like that. I believe it will catch some mercury as well if it is there.

 

[blueduck]

Classification, same sized particles, gold becomes the heaviest in the pan and gravity separation is easy. Various tools will get you there, a set of simple five - 5 gallon bucket screens/sieves on the big online yard sale site runs under $100us delivered..... Better built ones run higher, but the inexpensive set will help recover enough to further invest if warranted.

The way to move more material is with something designed for small particle recovery, the gold cube will eat a five gallon bucket of material from 5-7 minutes, generally faster than two people can rotate digging and feeding..... I seek those units like everyone else for just under $500us and that works out to about half ounce of gold to pay it off. For beach sand I personally have found nothing else that works better at this time in that price range, but there are new devices coming to market that may be as good or better this year.

If a person is handy, you can look into building a pop and son sluice which is basically a plywood sheet set at a steep angle with a set amount volume of water washing per degree of angle..... Gold as fine as -200 seems to stick but feeding it take awhile to learn..... Contact zooka on the yahoo group gold miners forum for his various test results using that design (may even be in the archives there)

Classification is the place to start, know the size of the material, and believe me I have seen gold stick in with that magnetite even when dry and dropped five or six times with a top hat magnet and picked up and moved..... Smaller gold will be caught in with larger metal as the magnet picks everything up and moves it.....


William

 

[rhwhite67]

Hematite tends to be para-magnetic. Get a neodium / rare-earth magnet off of ebay and put it in a plastic bag etc. it should normally pick up most of the magnetite just like a regular magnet will pick up the magnetite. Dry your cons first and spread them out thin so that you will not pick up much of the fine Au with the magnetite and secondly with the hematite.
Wish you the best in your separating it works but can be time consuming.
Ron

 

[rhwhite67]

Another option. make a small flat bottomed sluice out of plastic. coat the plastic in vaseline petrollium jelly. run your cons across almost flat with low water flow. Run everything 2-3 times. Gold sticks to the vaseline the Hematite and Magnetite will not. Rinse well. Use and plastic scraper to scrape the vaseline into a glass container and dissolve/dilute the vaseline until it is water thin. the gold will settle to the bottom, decant the solution off. place the gold in a stainless steel bowl, set the acetone soaked powder on fire and burn off the residual evaseline / acetone solution. Clean your now blacksand, Magnetite, Hematite free gold.
Sounds crazy but it works.
Ron