cyanide soultion question

[kjavanb123]

ok

I finally did it, my first ever test on using cyanide soultion on gold ore. After rolling the bottle for almost an hour, In a 300mL jar, I see the followings:

1. Top layer: foams about an inch width.
2. Yellow color clear liquid. about 3-4inches
3. Very tiny soil about 3-4inches. color light brown
4. larger particles at the bottom, about 2 inches.

Now does the Yellow liquid means it contains gold? Thanks.

 

[4metals]

Hmmmm.......

You have 9 to 11 inches of material in 4 distinct layers all in a 300 milliliter jar? Must be one long thin jar! Anyway the yellow liquid phase may be gold. On the other hand if you processed dried cow dung using the same process, the yellow liquid phase probably would not be gold. You need a few more steps to be sure. Color alone doesn't cut it on a leach.

Filter out the liquid.
Rinse the solids free of cyanide solution.
Collect all liquids and boil to get rid of dissolved oxygen.
Add powdered zinc to drop the gold and or silver.
Filter the soilds which drop out and rinse well
Outside with the wind to your back and NOBODY downwind add 50% HCl to dissolve the zinc. (that's in case you didn't rinse off all the cyanide, you see cyanide isn't very forgiving when mixed with acid)
The acid is then filtered off and the powder will most likely be gold if the ore had any in it.

 

[arthur kierski]

4 metals; i did a batch containing (e-scrap) gold with cianide--i filter and washed the scrap---to the liquid i added naoh (ph+-12)after shaking well and zinc powder was added--igot a powder(gold) but i did not eliminated the o2 ---i did not boil the solution---do you think that i extracted all the gold? if not ,what must i do with the cianide solution to extract the rest of the gold?

 

[kjavanb123]

4metals

On the other hand, after almost 12 hrs seeing that yellow color liquid in the bottle. It turned clear now hmmmm..what does that mean? I checked the pH level when it was light yellow in color, it was around 9 or 10. when checking the pH level of clear liquid after 12hrs it was 5-6.

 

[4metals]

The boiling is only a precaution to remove the oxygen in the liquid, a heavy alkaline solution with zinc should be enough to drop the gold. Sprinkle a little zinc in the solution and let it stand for a few hours to see if any more gold comes down.

 

[Platdigger]

At a ph of 5 or 6, wouldn't he be off gassing hydrogen cyanide or some such?
Randy

 

[kjavanb123]

ok

Now i did that test again, this time I removed the yellow part out of the test bottle, and drop 2 geranul activated carbon...wow..interesting...they got coated first with some small bubbles, then few larger bubbles emerged from the granule carbons. and they sank to the bottom...what the hell does that mean? I am going to try to test the yellowish liquid using the methods in Hokes book. This stuff are soo awesome.

 

[kjavanb123]

At a ph of 5 or 6, wouldn't he be off gassing hydrogen cyanide or some such?
Randy

I didn't open the bottle cap to test the pH. I just used a syringe to remove one drop of the clear liqiuid from the bottle then sealed the the hole with tape quickly. So I hope i didn't get any HCN.


My question is this. How come it was ph around 11 when the liquid was light yellow color..and after 12 hrs it turned clear with pH of 6? Does that mean I needed more lime? does it mean it didnt dissolve gold? the original ore I used in this experiement does not have any pyrite or calchopyrite.

 

[4metals]

KJ

Maybe I've missed it in another post but could you tell us exactly what you know about the material you are processing? What was the assay? What else is present? How much material is there to process? Why did you choose a cyanide leach?

From what I can gather you're working with mined material which has been ground to a fine powder, if it is unprocessed material, odds are it runs one-half an ounce per ton or less. So if you are testing a pound, you're looking for 0.007 grams or less of gold.

In that range you should be assaying the ore not leaching it. Give us something to work with here and maybe we can all learn something, but now we're just guessing.

 

[kjavanb123]

4metals

The ore I am working on is tailing from copper flotation plant. Estimated total of 5 million tons of tailing there. Original ore is mostly chalchopyrite and pyrite. I got 3 different assay results on the tailing. One from China stated 2grams per tons of Au and 70grams of Ag. Yet some of the engineer worked in mine since the begining told me that number is 0.5ppm for Au and 10ppm for Ag. Yet I gave 4kg sample from tailing to a chemist who used chemicals to recover gold and silver and as you can see from the picture it produces 0.173grams of Au, and 0.107grams of Ag. Now I wonder if that is much gold and silver in 4kg of that tailing...then does that mean that 1000kg of tailing should contain ( 250x0.173grams = 43.25 grams of Au and 250x0.107 = 26.75grams of Ag ) ?


Advise.

 

[4metals]

The copper flotation method that I am familiar with involved using a lime slurry and an oil to froth and float the copper. I find it hard to believe that after all of the efforts went into pulping the copper ore, especially 5 million tons, that they never noticed the gold and silver. Tailings piles are one of those things that are hard to sample representatively. I suppose if you had a bobcat bucket loader and spent a day digging and moving and collecting loads from around the pile, then you coned and quartered it, you MAY get lucky enough to have a sample that represents the pile. Still it isn't a certainty. Usually guys that sell tailings piles learned their trade from the guy who was trying to sell that bridge in Brooklyn. Your first question to the seller is this; How did you get the 4 kg sample, and how do you know the entire pile is like that sample? Generally, for some miraculous reason I could never understand, the samples always have gold in them. The big pile is another question.

Concerning your math, you are correct, that the material IF IT IS CONSISTENT THROUGHOUT THE PILE will yield over one ounce per ton of gold. Commercial ventures involving excavating, crushing and leaching have prospered on lower yields per ton, so it begs the question; Why are they marketing it to a newcomer to the industry when larger concerns, with capital to extract the metals and experience to do it would also be interested?

That bridge in Brooklyn is still on the market!

I just noticed this as well, the photo you included shows solid metal. If the assay extracted the metals they would be in sponge form and usually the silver would have been calculated by difference. I've never seen or heard of anyone melting that small a quantity of gold, and the guy who did it for you even separated the silver and melted it as well. It's good that you are asking questions, now go ask a few of the seller and the assayer and let us know what they say.

 

[kjavanb123]

4metals,

Thanks for your respond. As for the copper flotation they use the pine oil, and some other oils to do the copper ore processing. I wonder the gold and silver in the ore get extracted with that oil used in copper processing? the dude who has worked there all his life told me yes, others are telling me no lol..

I actually took the 4kg sample myself, from different layer, guessing 3meters in height from the tailing. this time for sampling I am gonna use a teaspoon and collect samples from all over the tailing dam which is a wide area this should roughly represent the average Au and Ag grade through the whole tailing pile.

The dude who got the gold and silver dots from the 4kg, is not an assayer, he is just a practical dude who knows how to extract metals using chemicals.

One thing that amazes me is that he did extracted gold and silver from 4kg and 67kg samples provided to him. So I can assume there is gold in the tailing yet to be economical. Also there are few companies I was in contact with that they processes tailing dumps all over the world and could get the gold out of them. Even tailing from gold refining plant

So I will keep you guys posted.

 

[4metals]

When copper is extracted from the pulp by flotation, all the PM's come along with it. The frothing concentrate is melted into bars and refined electrolytically, producing electrolytically pure copper and leaving the PM's in the anode bags as a slime. I'm sure some metal is left behind, there's no large scale extraction process that I have ever seen that gets everything.

Like I said, getting a representative sample from 5 million tons may be impossible. Based on the numbers you have given the pile would have over 6 million ounces of gold remaining if your sample and extraction were accurate. With that kind of value one would expect a lot of activity around the site given today's gold prices.

 

[kjavanb123]

4metals,

This plant ONLY produces copper concentrate (20% Cu) and there is another factory that produces 99.9% Cu.

One thing that get me confused is why 4kg and 67kg have gold and silver.

 

[4metals]

I'm sorry, what I said may be unclear. The flotation process produces a concentrate and in the process of producing the concentrate the gold and silver were left behind. It's the flotation process that missed the metals.

The copper concentrate (20%) is then electrolytically refined either at the same place or in this case at another factory. This is where the PM's are recovered from the slimes.

 

[kjavanb123]

4metals


how can you explain the 0.173grams of Au and 0.102grams of Ag from 4kg?

 

[4metals]

I'm not doubting that the sample you presented to the chemist had the metal he reported. One has to wonder feasibility of 5 million tons having the same assay. Do the math, it's a billion dollars worth of gold alone. Historically in the world mined material runs less than 1 ounce per ton for gold. This has been processed and it exceeds that. Is someone trying to get you to invest in a recovery operation? What is the relationship with the chemist who processed the sample? What does he have to gain from your investment?

Gold can get to be a fever, the lure of the quick fortune, and because of the lure people are out there trying to scam anyone they can. What are the odds of you stumbling on to a billion dollar pile of prepared ore waiting to have the gold extracted? Maybe it's true, if it is God bless you, but odds are someone is trying to profit off the fever, be aware and don't get caught.

 

[goldsilverpro]

I agree with everything 4metals has said. A grab sample would be next to worthless in this case. All the assay shows is what is in the sample, assuming that the 4 kg of material, itself, was properly sampled. Even your teaspoon method sounds very, very unreliable.

So, what is the best way to sample the material? Maybe, hundreds of deep core samples, each of which being properly prepared, sampled, and assayed. Then, some statistical numbers could be determined. Even then, there would be some statistical doubt.

Sampling is difficult. Assays are easy. Assays only tell you what is in the particular sample.

 

[kjavanb123]

guys,

The chemist I gave him the 4kg and 67kg samples from tailing didn't know anything about where these samples came from. I just simply asked him if he can extract gold/silver from this soil. He did it 2 times once with 4kg samples, and other times with 67kg samples.

However I have collected different grade information from engineers worked at the mine, owners, Chinese lab and another assaying companies to add to confusion.

I have asked the chemist to remove the PM from another sample tailing, in fornt of me, so if it is possible. I guess to setup a pilot cyanide leaching plant that process 10tons a day wouldn't be that expensive. Once we process enough stuff then we can expand.

Could this chemist dude just for heck of it like added some gold and silver to make me feel good about tailing?? that just puzzles me all the time..if he couldn't find any gold..why wouldn't he tell me...knowing that he has no idea where the mine is or how these tailings are produced?!!

 

[4metals]

KJ

If you're going to set up a pilot plant anyway, I doubt you'll move 10 tons a day with a wheelbarrow so you'll need a loader. If you have access to a loader, use it to dig random holes which you should sample, take 1 pound out of the top of the hole, the middle, the bottom and repeat this for at least a few dozen holes. Now either mix the samples together and cone and quarter them and send a sample to a lab here in the states. If the samples you send comes back with payable gold, go for it. But it is imperative that you break the local loop and send to a lab in the states, then there's no collusion that you're not being told about.

You can also jar leach a sample and send it to a lab to have the solution analyzed.

If you are out of the US, and you're working with locals, you're the odd man out. I set up a leach operation in Zaruma Equador once in the eighties and the only place I could get straight answers was from a lab stateside. I was a gringo and that's all they knew, the perception is all Americans are loaded!