# Help, I'm new in this area



## Oscarpastcer (Jan 29, 2011)

Hello, I'm Oscar, nice to meet you all I readed a lot of posts here, and I'm amaze all the information and help with other users, I want to congratulate the moderators and members.

Well, after that presentation, I want to talk about my problem. Recently I started to try to refine Au, I did my research and I found a process doable with the things I have, this process is Igoli, but a few days ago I finished the process and I couldnt precipitate any gold, in the samples there is gold, because the person who give me the sample used to work with the process of Hg, and find gold, and I want to change that process because the danger of that chemical.

I want to describe what I do.
First, I took the sample, and I leached with HCl diluated at 15 %(I used HCl about 37% of purity)
then I put about 0,2 lt of HCl diluated with 0,1kg of the sample
I stirring about 10 min and I added 50 ml of NaClO and after 20 min I added 5 ml od NaClO for 5 hours stirring
I separated the liquid/solid with a centrifuge and I found a solution colour green with yellow
This solution i put it in a vessel and put like 5 gr of metabisulfite (Na2S2O5)
And I wait all the night to precipitate, in the mourning I couldnt found any precipitate

These are my questions:
With my explication, is that ok? or did I do something wrong?

I realized I could find any precipitate because was a small sample, I gonna doit again with 1 kg, is there a posibility that the problem was the small sample?

How many grams of metabisulfite I need to add for 1kg of sample?

The method that I used to separated liquid solid, was a centrifuge, is that right or I need to change that method, like vaccum filtration?

The final question, are you recomended this process or you know any other?

Sorry for my english, but it is not my mother language.

Thanks for your response.


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## eeTHr (Jan 29, 2011)

oscarpastcer---

Welcome to the forum.

If someone has an idea that they think might be of help, it would benefit you to list your approximate location in your personal settings, in the User Control Panel, so they might suggest process with chemicals that are more likely to be available in your area.


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## samuel-a (Jan 29, 2011)

Welcome to the forum Oscarpastcer 

I'm sure that eventually you will find your answers here, either by digging the archives or by asking questions.
It's obvious that you put much thought in your process and question but you left out the most essential part; What kind of material did you tried to process ?

please understand that providing details will help others help you.

Good luck .


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## Oscarpastcer (Jan 29, 2011)

The material is soil, i dont know exactly what do you mean, with type of material, is Au there, because like I said in the post, the gold was extracting with Hg mercury.
Soil with a lot of water and other materials


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## FrugalEE (Jan 29, 2011)

I did a google on Igoli and got this:

THEIGOLI MERCURY - FREE GOLD EXTRACTION PROCESS Sidney Mahlatsi, Senior Engineering Technician: Mintek - Small Scale Mining Division ABSTRACT; Mintek has developed a process called iGoli Mercury-free Gold Extraction Process that can be used to extract gold from 0.1 % gold concentrate to produce 99.90 percent gold product. The process uses a mixture of pool acid (dilute hydrochloric acid), bleach (sodium hypochlorite) and sodium metabisulphate to leach and recover gold.

So the chemical process is the same as used by quite a few board members.

FrugalEE


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## carcrossguy (Jan 29, 2011)

You might want to make some stannous chloride to test if you have any gold in the solution. you need hcl and a bit of tin. I used 95% tin solder.

Some people say mercury is not very dangerous as long as you are knowledgeable and smart about it. Making a retort appears to be very easy.

http://www.goldnscrap.com/index.php?option=com_content&view=article&id=63:stannous-chloride-test-for-gold-platinum-and-palladium-presence&catid=25:scrap-gold-9k-24k&Itemid=20


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## Barren Realms 007 (Jan 29, 2011)

FrugalEE said:


> I did a google on Igoli and got this:
> 
> THEIGOLI MERCURY - FREE GOLD EXTRACTION PROCESS Sidney Mahlatsi, Senior Engineering Technician: Mintek - Small Scale Mining Division ABSTRACT; Mintek has developed a process called iGoli Mercury-free Gold Extraction Process that can be used to extract gold from 0.1 % gold concentrate to produce 99.90 percent gold product. The process uses a mixture of _pool acid (dilute hydrochloric acid), _bleach (sodium hypochlorite) and sodium metabisulphate to leach and recover gold.
> 
> ...



Your comment about pool acid is incorrect. It is regular strength acid.


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## Oscarpastcer (Jan 30, 2011)

So, i dont have to diluate the acid?


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## Barren Realms 007 (Jan 30, 2011)

Oscarpastcer said:


> So, i dont have to diluate the acid?



I can't answer that question for you because I am not sure of what you are processing. I was just informing you that the acid sold in pool supply store is generaly 32%. Not diluted like you said.

Some pictures of what you are processing would help a lot.


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## Oscarpastcer (Jan 30, 2011)

Ok, this monday ill take some pictures, I said diluate because the paper of mintek about igoli procees, said that, diluate at 15% the pool acid (HCl)


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## Claudie (Jan 30, 2011)

I am just trying to understand here but, this is a soil sample you are trying to refine?


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## Harold_V (Jan 30, 2011)

It is my opinion that you have processed way too little material to achieve a recovery. Unless you are working with extremely high grade ore (dirt), it's unlikely you will be able to recover gold profitably.

Lets look at it this way. I'm going to assume that the ore you have at your disposal contains a troy ounce of gold per ton. I'm also going to assume that you used as your sample, a pound (slightly less than a half kilo). Assuming it assayed an ounce/ton, and assuming you were successful in recovering all of the gold in your sample, you would have recovered less than ¼ grain of gold. It's highly unlikely that you'd be able to see it if it was there. 

It would help tremendously if you could talk about the concentration of the ore in question, and how much you processed. You haven't provided enough information for anyone to form a reasonable conclusion. 

I'd like you to keep in mind that processing ores with acid is rarely successful. 

Welcome to the forum. I paid a visit to Venezuela back in '78. Beautiful country. 

Harold


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## Oscarpastcer (Jan 30, 2011)

Thank you all, for your valuable help and responses.
Harold, the concentration is around a troy ounce of gold per two pounds of soil.

I have a question, about this process, Igoli, does anyone had work with it? and if this process is really effective like the minetek say ?

I cant work with Hg, because here is very expensive, thats the reason.

By the way I'm recently got my grade of chemical engineer, about 2 weeks ago =)

And yes Harold, Venezuela its a beautiful country


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## patnor1011 (Jan 30, 2011)

If using mercury retort you will lose very small amount of mercury.


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## eeTHr (Jan 30, 2011)

Oscarpastcer---

What is the exact nature of the material you are calling "soil"? Is it crushed rock from a mine, or acutally organic soil like would be in a garden? Or is it sands from a placer deposit?

That could make a big difference as to the best methods for processing it.


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## Oscarpastcer (Jan 30, 2011)

eeTHr said:


> Oscarpastcer---
> 
> What is the exact nature of the material you are calling "soil"? Is it crushed rock from a mine, or acutally organic soil like would be in a garden? Or is it sands from a placer deposit?
> 
> That could make a big difference as to the best methods for processing it.



The origin of the soil it is from a deposit with rocks, and it is crused, fine soil, tomorrow ill take a picture of the sample


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## Oscarpastcer (Jan 30, 2011)

Claudie said:


> I am just trying to understand here but, this is a soil sample you are trying to refine?


Refine, no I'm trying to extract gold from the soil, i think my post is out of place here, could a moderator change my post to the proper area please?


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## eeTHr (Jan 30, 2011)

Oscarpastcer---

OK, so what you really have is crushed rock ore. The term "soil" usually refers to the kind of dirt that people grow flowers and vegetables in, and contains lots of organics.

How fine is it crushed? Is it as fine as powder?

It would help if you include a few pieces of the original rock ore, when you post pictures of your material. The type of rock may help determine what would most likey be the best leach type.


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## Harold_V (Jan 31, 2011)

Oscarpastcer said:


> Thank you all, for your valuable help and responses.
> Harold, the concentration is around a troy ounce of gold per two pounds of soil.


Wow! That's' VERY good. Can you tell us how that number was achieved?



> I have a question, about this process, Igoli, does anyone had work with it? and if this process is really effective like the minetek say ?


I'm sorry to say, all of my experience with ores came with cyanide and bromine. I am not a chemist, and am unable to make a fair judgment on the process. 



> By the way I'm recently got my grade of chemical engineer, about 2 weeks ago =)


Congratulations! I commend you for the effort it must have taken. 

Please give us more information on your project so we can gain a better understanding. You've already mentioned posting pictures. They should help considerably. 

Harold


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## Claudie (Jan 31, 2011)

You stated that the concentration is around a troy ounce of gold per two pounds of soil. If you are doing a 1kg sample (which is what you asked about) that would work out to about 2.2 pounds of material. So that should mean there is over one ounce of gold in your sample. 

May I ask if you purchased this sample from a trusted source or have you seen any assay results? Please forgive me if I am asking unusual questions, I am just trying to understand for sure what you are dealing with. With an ounce of gold in a 1kg sample, I am thinking you should be able to find it. Maybe my math is wrong or maybe I am misunderstanding something.


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## carcrossguy (Jan 31, 2011)

Since when is mercury expensive in Venezuela. The internets says it is cheap and readily available there.


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## eeTHr (Jan 31, 2011)

Oscarpastcer---

If you have an ounce of gold per kilo, you should be able to _see_ the gold in there. If it's too small to see, use a magnefying glass. And you could just _pan_ most of it, in an hour or less for a kilo. One ounce per hour is pretty darned good, unless you have tons of the stuff.

If the gold is very, very, tiny, you could probably just put water in there and _float_ most of it.

If it's a little to big to float, you should use a Miller table.

After that, refine it if you want. That way, you'll know your purity, and can't be fooled.


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## Oscarpastcer (Feb 3, 2011)

Hello again, well I'm posting the pictures =)







After that pictures, I want to show you some pictures about the process, first the leaching process. with HCl and NaOCl at 50°C and about 4 hours
¬



After the leaching process, I separate liquid/solid and the liquid was this, I't supouse to be gold in solution there




After that, I added meta bisulfite to precipitate, but there wasnt precipitate, and the colour turn in green




The metabisulfite, is old, I dont know if theres a posibility to blame the chemical, or the process, or the sample, but the sample has gold, because the sample has worked with mercury amalgam and extract gold.


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## Barren Realms 007 (Feb 3, 2011)

Have you tested with stannous?


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## Oscarpastcer (Feb 3, 2011)

Barren Realms 007 said:


> Have you tested with stannous?



Yes, and the test, was positive


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## Barren Realms 007 (Feb 3, 2011)

Do you get any smell when you add the SMB? does it have clumps in it idictaing that it might have come in contact with moisture? You can mix some up in water and wave your hand across the top of the container towards you and see if you get an odor but be careful doing it, and don't take a deep breath when doing it.


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## HAuCl4 (Feb 3, 2011)

Oscar: Have you performed a fire assay of your sample to verify that there really is gold in that particular sample?.

Is the material from your mine or someone else gave it to you?.

Put a piece of copper in the liquid and if there is gold, it should drop as a brownish powder. Silver will drop too.

If you are going to do this in a big scale, cyanide is a better way to go.

I'm in Caracas, by the way. 8)

edit to add: If those concentrations of 1 Oz per Kg are true, those are very high grade concentrates. Standard procedure is to smelt them and produce a clean dore bar, before further refining.


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## carcrossguy (Feb 3, 2011)

I can bearly see any yellow in the liquid 60 ml. Should be darker if there was substantial gold.


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## Lost_Adams (Feb 8, 2011)

Oscar, 
If there is 2.2 oz of AU in a Kilo of "soil". 
This can be verified by taking an oz of the material and mixing with equal
amounts of either Baking Soda (CHNaO3) or Borax (Na2B4O7·10H2O).

http://www.geus.dk/program-areas/common/int_ssm_fact_sheet_07.pdf

These are fluxs and work fine on any charcoal source. ie Barby Briquettes 

You should get a small bead of Au from 30gm of material that weighs>>
1 kilo = 15 432.3584 grains
15 432.3584 grains / 1000gm = 1.5432 grains per gram ed(15.5432 gr)
30gm sample of soil x 15.432gr per gm = 462.96 grains
462.96gr/ 15.432gr/gm = 30gms
462.96gr / 24gr/dwt = 19.29 dwt 
In inch's this would be a Sphere about .566 in dia. 
this large a sphere would SQUAT and take on a flattened shape,
To visualize the size of a grain of gold in spherical form 
it would be 0.073" inches. This corresponds to the Size of a #9 lead pellet in a shotgun shell for shooting Birds. 

Hope this helps!
Sincerely
Bill Adams

Just noticed my calcs were off by a decimal point Sorry About that it was late when I posted that response. (3-29-11)


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## dtectr (Feb 8, 2011)

Did you have to pay anyone for this information and/or sample?

make sure you're using "sodium metabisul*FITE* as a precipitant, not -bisul*FATE* . just a thought ...

EDIT: has anyone checked out "Mintek"? http://www.mintek.co.za/index.php


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## Oscarpastcer (Feb 9, 2011)

dtectr said:


> Did you have to pay anyone for this information and/or sample?
> 
> make sure you're using "sodium metabisul*FITE* as a precipitant, not -bisul*FATE* . just a thought ...
> 
> EDIT: has anyone checked out "Mintek"? http://www.mintek.co.za/index.php


Yes was sodium metabisulfite, N2S2O5


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## Oscarpastcer (Feb 9, 2011)

Thanks adams for your information. I'll put in practice


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## Lost_Adams (Feb 9, 2011)

Oscar, I lost my post and don't want to retype it. here is a link to something you may want to check out. 

http://www.butlerlab.com/

If you want the Excel Spreadsheet, I made, on the size of gold beads and theirs weights from 0.001" to 0.50" in 0.001" increments just give me a PM and I'll send it to you. 
Sincerely
Bill Adams


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## butcher (Feb 12, 2011)

the green solution looks more like base metals than gold solution, although a stannous test may show positive it will show positive for very low concentrations of gold.

I feel you may have leached base metals.

assay your solids.

base metals will leach before gold will, and if you still have base metals in the "DIRT" you still have any gold in those solids.

what pretreatment did you do to this ore? what base metals and what state are they in in this dirt? 

for that green solution I would try using copper to precipitate any values, instead of using sulfite, if any precipitate formed then I would retreat it.


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## wildbill_hickup (Mar 26, 2011)

eeTHr, 
I'm with you. I would try panning first. Water sure is cheaper that all those acids, etc. At the concentration he is talking about even a handfull should leave dust in the bottom of the pan. I'm certainly no expert but I have done some panning up here in Vermont and New Hampshire and I have spotted some pretty small flecks of gold in the pan (don't make anymoney but it's fun) As you said you should probably see some gold just by looking at the sample. 1/2 ounce per pound. I'd concider myself lucky to find 1 grain in a pound here. Even if there were alot of heavies in the mix I would guess that panning would at least reduce the volume of materal some. To me there sounds like something is wrong here. :roll: IMHO


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## Oscarpastcer (Mar 27, 2011)

Hello, well I was focus in the lab, trying to recover some Au, but with no success, uhm I dont know which is the problem, I use HCl at 30% and add NaOCl at 10-15% about 5 min.

The sample of the crushed rock, this crush is about under the 150 micrometers.

The leach is 150 cc HCl and adding 5 cc every 5 minutes ten times, in other words 50 cc of NaOCl total.

A minerologist told us that in the rock was Gold, she doesnt know how exactly it is, this week I'm going to do an SEM (scanning electron microscope), to knowe the quantity exact of Au. 

If, the AuCl3 after put some SMB, turns in a solution clear, almost transparent, its that ok, I dont know if the solution of SMB is correct, also I use the stannous cloride test, but I have my doubts. The stannous cloride solution is need to be all diluated, I mean clear transparent, or it is okay if is milky (white) like Hoke in his book says.

Does anyone one can help me whit this doubts please.


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## butcher (Mar 27, 2011)

Gold in ore can be a complex of metal salts, (acid + base or metal = salt), most all leaching will need pretreatment of ore, usually concentration, and roasting, sometimes additive are added to the roast to change the metals chemistry, base metals are usually removed before values, sometimes the chemistry of base metals can make leaching almost impossible till you convert their chemistry.

Ammens book is very good read for Ore, got mine from action mining up north of here in Oregon.
Also some of the old mining books are a wealth of information.
I would look into assay, and determining the chemistry of your ore, then look into way's of dealing with these.


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## Lost_Adams (Mar 29, 2011)

Oscar, Have you done the fire test with the assay and the borax???
If so what was the result???
This is a Difinative test for AU in any form. If it's in your sample you will get a Gold metalic bead that will be an alloy. 
If you DO NOT get a bead then your sample HAS No AU or so little that you lost it in the crushing and panning part of the processes.
You will then need to question the people who are telling you that the SAND has GOLD in it.
No matter how much we want to wish or hope we have RICH concentrates or head ore it is just not always true.

I have a man who says he is going to pay me to come and dig up his gold he has on this property. He has said that I can have a share, but I told him I didn't want a share, but I just wanted my wages for doing the sampling work. He said that he would give me a bonus WHEN we found the AU. 
When I looked on the Geologic Maps of the area I was able to ID a potentional Ancient River Channel very near there with a possible feeder on his property. But then I saw that the Lake behind the dam was at 280' elevation. The Highest point on his property was 350' and the lowest 320'. So even IFFFFF every thing else is a go then we will hit WATER at 40' and will have to start pumping. NOW this wouldn't be a problem normally, BUT there isn't enough land to make Setteling Ponds to clarifiy the water befor it goes into the Lake. And this is all AFTER THE PROPER PERMITS AND ENVIRONMENTAL IMPACT STATEMENTS are gotten.

But I'll still do the sampling and give him my report and receive my wages and expenses for my work.

Sincerely
Bill Adams


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## Oscarpastcer (Mar 29, 2011)

Thanks Adams for your answer, and about your question, no I havent, I havent do the fire test yet, I read Ammen and I found it how to do it, and I will do, when I got the result I'll let you know thanks


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## Oscarpastcer (Mar 31, 2011)

God day, I have some concerns, I think my gold isnt precipitanting beacuse there is Cl in the solution, ok what I have to do is boil the solution, but how much boil? the frist bubbles? or Ill have to wait a lilttle more? after the boiling i diluated the solution 3 times with water? and after that ill put the SMB?


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## acpeacemaker (Apr 1, 2011)

From what I understand since I have just been reading and not doing "yet" is you have to boil out the chlorine. Also, there is a lot of expressed concern your not actually boiling but evaporating. And the chlorine gas is not something to breathe in. It will take your breath away. -Andrew


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## Oscarpastcer (Apr 1, 2011)

acpeacemaker said:


> From what I understand since I have just been reading and not doing "yet" is you have to boil out the chlorine. Also, there is a lot of expressed concern your not actually boiling but evaporating. And the chlorine gas is not something to breathe in. It will take your breath away. -Andrew



Thanks for your concern Andrew, yes I know but I'm evaporating the chrlorine under a hood, sorry for some problems with some words in english, because that isnt my mother language. But when should I stop from evaporating?


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