How can I process gold-rich silt and other items

[dehaas99]

I'm new and I'm not a chemist keep in mind.

I have some silt collected that contains gold. Very little sand. Collected by stirring up water between rocks and collecting the stirred up water with a zip-loc bag, let everything settle, squeeze out excess water, repeat. Rocks and sand are mostly eliminated using this process, and the rock and sand collected later. What's left is a dark brown silt/dirt loaded with "glitter". Larger specimens from this area tested positive as gold.

One method I used to eliminate the silt was to break up the dirt particles in a bleach solution and then transfer the material to a muriatic acid and hydrogen peroxide solution over night. Added lots of water to dilute the acid and allowed the material to settle to the bottom before draining as much of the water as possible and put it on a stove to slowly evaporate the water. Resulted in a nice, powdery substance gold in color.

Second method, which included processing material along with small rocks and sand mixed in: Did the muriatic acid/hydrogen peroxide with some results. Seemed to dissolve the gold into a fine cloud leaving the larger rocks and a lot more sand. Strained out rocks and some of the sand and re-treated that material. Did not use as much water this time to dilute the acid, which when heated turned everything into a dark brown color. When evaporated I'm left with a crusty dark brown material.

Question "A" is this: Is there a way to quickly and easily separate the gold material from the silt so that I can collect quantities of it at a time, further refine the dirt out of it on-site so I'm carrying less material? Would incinerating it with a small-scale setup help burn off the dirt/silt and help to concentrate the gold material?

Question "B" is: With the sand/rock situation I'm sure that I must have dissolved some of the gold. I have the water and all of the material. How can I recover the dissolved gold and how do I get the crusty dark-brown by-product of "over-cooking" the gold/acid solution turned back into a refined gold? All without expensive processes or anything that will create deadly fumes. Many of the rocks in this case have fragments of gold in them. I've considered crushing them and then processing them the same as if I were working with sand.

I only travel to the location where I found this gold once or twice a year and it's a really remote location so my on-site resources will be limited. I can't carry out bags and buckets of dirt, sand and rock. Lots of the gold material is too small to effectively pan (maybe I'm not the best at it?) so the sand and dirt require a better processing method without losing gold content from the material once it's collected. If I can learn how to even take a single step in reducing the non-gold material it will go a long way. I'll be glad to show a picture of the gold/silt material as it looks after it's collected if that helps.

In the end I would like to be able to melt down the gold and incinerate the additional material to refine it to at least a 95% purity or better.

I will appreciate all/any feedback. I'm experimenting with this material I brought back home and only have a limited supply to work with. If I can get to a 99% refining stage with the material with your help I'll follow up the question to share how much I ended up with and a picture. Thanks!
-D

 

[Richard36]

Hello dehaas99,

Welcome to the forum.

It's obvious that you have much to learn about refining yet, so I suggest that you spend some time studying, and reading related topic threads here. Aside from that, I'm not all that convinced that what you have is actually gold, but if so, run that material through a sluice box, and collect all the heavy sediments, then get an assay on it to prove gold content, then proceed with your efforts to recover the gold from within it, if indeed your material does contain gold.

Aside from all that, if that glitter moves around in the water with ease, then it is mica, and not gold.
If it crumbles when crushed, it's a sulfide mineral such as pyrite.

Collect some of the suspected gold, and dissolve it in Aqua Regia, then in a separate vile, dissolve a snipping of tin/lead solder in Hydrochloric Acid (Muriatic Acid is the weaker form) to produce Stannous Chloride solution.

Dip a q-tip in the aqua regia, then put a drop of the stannous chloride on the end dipped into the AR.
If the tip turns purple or black, then the solution does contain gold.

You would be wise to do this test before you proceed any further,
because if you don't, you may well dig yourself a money pit with no return for your efforts.

Wise words of caution from someone who has made a similar "Greenhorn Mistake".

Sincerely, Rick. "The Rockman".

 

[tlcarrig]

First, since you are doing your work in the creek, you need to go to different forums. You need to join the GPAA forum (you don't have to be a GPAA member to join) and at least take a look at the Alaska gold forum. The first advice you wil get is to join a local prospectors group. Most groups do not require that you be a GPAA member either. They are a wealth of good information and friendly people. There you should learn gold panning. This should be the most important skill to develop since you are working in the "wild". Then learn how to read a creek. this will alloy you to move around in your area for more gold because your "honey hole" will run out eventially. After learning to pan, go for a sluice so that you can move more material. Believe me, to get gold you have to move dirt. Once you catch "the fever", the sky is the limit as to the equipment available to you. Good luck.

 

[sawmill]

OK here is your first clue.
If you have gold large enough to be visible,you can
concentrate it in a pan,or sluice fairly easy. If it doesn't
settle to the bottom,its probably not gold.

I won't even go in to the chasing silt with a baggie
thing. :shock:

Under strong magnification the tiniest grain of native
gold looks the same as larger nuggets found in the same
area. Classify your material ,so the suspected gold is the
same size as the grains,of sand or dirt. If it is gold, it will
be the heaviest ,and concentrate from the other material,
regardless of size.

 

[dehaas99]

Thank you for your replies. Yes I'm really new to this and was weary of whatever I was finding so I didn't take much time to collect what I have. When I pan or swirl the material in a pan the fine gold material separates into tiny little streaks along the edge but it takes quite a long time to swirl it around and collect the concentrated gold with an eye dropper a little bit at a time then begin again. It's pretty fine stuff. I promise to share the results of what I collected in the "baggie thing" and fully admit I was wrong it I turn out to be.

The material that I have acid tests to 22 carat or better so far, even the material collected in the baggie from stirring up water. The location where I found this is in Canada on a lake feeding into a river. This is an area known to have gold and still I was skeptical. That in mind, I'm not surprised it was actually gold but now I'm disappointed I didn't collect more of the material. I wasn't there to prospect at all. I was there to fish. The two flakes to the right in the picture were in the dirt and rocks between two large rocks I was standing on to fish and literally looked down and saw them in the water. The material on the left has some sand and other material in it but also tests out to contain gold. Most of the powdery material was found in another location about 1/2 mile away from where the flakes were found and was literally sparkling in the rocks and dirt. The powdered substance was the result of soaking in bleach then solution of muriatic acid and hydrogen peroxide for a little less than 24 hours then evaporated to a powder.

The powder looks fit to melt and see what I have left but I don't know if this is the proper next step. I don't know (thanks for telling me how) how to see if there is dissolved gold in the solution I used. Will I need to find some hydrochloric acid or will the muriatic acid do the trick? I have a 96/4 silver bearing lead free solder. Is this the type I need?

I will test and update tomorrow time permitting. Thanks again.

 

[Richard36]

You need tin to make stannous chloride.
I mentioned tin/lead solder simply because that type of solder is readily available as a source of tin.
Hydrochloric acid, as well as muriatic acid will work.

 

[sawmill]

Now for the good news. Congratulations!
You have some typical placer gold.and it is of a size that
a sluice or pan will work great.You don't need no stinkin
acid or chemicals. :lol:

Run your dirt through a sluice or high banker sluice to
concentrate your gold in volume. Just use the pan to
separate your concentrates or test new spots. There is
several refiners that will buy clean placer gold. There is
no need to melt it .

A high banker sluice would grab that stuff with ease. Just
remember classify,classify,classify, when working with fine
gold.

Here is an old prospectors trick for retrieving fine gold
from a pan. Eye droppers and suction bottles are just a pain
in the butt,lose gold, and will drive you nuts. Drain all the water
from your pan while leaving the gold . Fill a pill bottle or vial
3/4 full of water . Lick your finger and press it into the gold.
The saliva on your finger will retain the gold. Dip your finger
into the bottle or vial ,and the water will release the gold.
You can get even the microscopic stuff like this and every
grain. Do this over the pan ,in case you have a spill,and you
won't lose any gold.

 

[Dirtdiggaler]

Now for the good news. Congratulations!
You have some typical placer gold.and it is of a size that
a sluice or pan will work great.You don't need no stinkin
acid or chemicals. :lol:

Run your dirt through a sluice or high banker sluice to
concentrate your gold in volume. Just use the pan to
separate your concentrates or test new spots. There is
several refiners that will buy clean placer gold. There is
no need to melt it .

A high banker sluice would grab that stuff with ease. Just
remember classify,classify,classify, when working with fine
gold.

Here is an old prospectors trick for retrieving fine gold
from a pan. Eye droppers and suction bottles are just a pain
in the butt,lose gold, and will drive you nuts. Drain all the water
from your pan while leaving the gold . Fill a pill bottle or vial
3/4 full of water . Lick your finger and press it into the gold.
The saliva on your finger will retain the gold. Dip your finger
into the bottle or vial ,and the water will release the gold.
You can get even the microscopic stuff like this and every
grain. Do this over the pan ,in case you have a spill,and you
won't lose any gold.

That is a great idea about licking your finger and dipping it in water. I have been trying to get small pieces of minerals out of my pan to test and I was having
a hard time. thank's

 

[blueduck]

Gold being 19 times heavier than water will not "float" in a plastic baggie for the most part..... the exception i have found is on the Salmon River here in North Central Idaho where the gold seems to be encapsulated in a glass substance.... which makes it float right on out of a sluice or any other device so far that i have tried.... yes some will lay down but 99% of it goes right on past.

If you've got decent placer gold like your picture shows you can catch it in mass quantities with the right sluice, power sluice, reverse spiral wheel or tube..... it all depends how much material you want to move and how much funding you have to set up.


If all you have is a pan, and your gold is small that you are recovering, you need to classify the material through a #8 screen or 8 mesh, and check the bigger stuff for the large nuggets very easy to pan that out btw, if you want to see a really decent Gold Fever show on the subject the GPAA has one online that you can watch for free right now called "backyard prospecting" it aint hard to put together a set up like Ralph has in that video.... if they ever take it down its #98GF and the DVD is only like $14 and well worth buying so you can study what he is saying and doing.....

Once you get the classification started you can process the smaller and smaller gold out without using mercury if you desire by purchasing various size classifier screen, and pan each size out separately.... when everything is the same size, gold wins the battle for the bottom......

one tst you can make is when the "sparkly" material is laying in your pan where you can see it if you pass yer hand over it and shade it from the sunlight, gold will not change color, while mica will .......

Look on my website and if you see anything there you want information about, ask.... recovering gold dont have to be expensive, you can build most tools you need or modify some tools you already have to make them work [its how some commercially available tools came to market] a good pan and classifier and a snuffer bottle are under $50.00 add in a shovel, a small pry bar whisk broom or paint brush and a small garden trowel and a couple 5 gallon buckets and even if you have to go out and purchase everything new its under $100.00 and at gold prices a gram of gold is pushing $60.00 [he price you get when you sell will vary greatly between buyers] add a sluice for another $120.00 or less and a 12 volt pump for another $40.00 and yer still under $300.00 but you double to triple the amount of material you can move in a day of playing in the crick. if you have really fine gold like under 30 mesh then i recommend the Gold Cube which will catch that really fine old even in the range of -400 mesh and that is small enough you cant see it without magnification and you need to classify the material after its run to concentrates into the various screen sizes available to you..... again same size particle and gold will all gather together in your pan.

Listen to what Richard and other folks say about acid being the wrong way to go first, if you dont have to..... and you will find that big yellow smile in your pan!


William
Digg It Prospecting Supply, LLC
Idaho

 

[Palladium]

Well look what the cat dragged in. :lol:
How life treating you Duck?

 

[blueduck]

Well look what the cat dragged in. :lol:
How life treating you Duck?

life is good.....
Happy Birthday Ralph, yer the reason i showed up here today.... yer profile on FB said this was yer personal civil entry date! so i found a thread i could set my three cents worth into [inflation since the big "o" took office ya know]

Anyhow
I hope that folks understand that even though i dont post often, i try to be helpful and I aint just trolling for customers.... i'd rather help someone out with a problem and NOT sell them something they dont need or cant use than sell someone something they just set on a shelf or grumble about. Finding gold in the wilds is awesome and fun, high water this year wore on til about 4 weeks ago when we could finally hit the river here, and then i had a eye tooth pulled out and was down for awhile water is still colder than it normally is this time of year...... but the water brought down more gold and its closer to home this year on the beaches...laying there for the right fella to pick up and put to use.

William
Idaho

 

[Palladium]

We all love to see you drop by duck and i understand your position as far as participation on the forum goes. Glad to hear all is well with you and yours. Thank you for the birthday wishes.