Copper dissolves while cementing.

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Hello Guys
I have reading this blog for very long time
and I learn a lot
I'm following many members posting
And I do my own cement out
and this what i get
i put a piece of copper pipe
and i get a black powder
 

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Hello Guys
I have reading this blog for very long time
and I learn a lot
I'm following many members posting
And I do my own cement out
and this what i get
i put a piece of copper pipe
and i get a black powder
Nice, do you have a question?
The black sludge is your values, but they need refining.
 
It have to be tested.
Simply redissolving and testing with stannous will give some answers.
A full assay will tell the whole story.
 
It have to be tested.
Simply redissolving and testing with stannous will give some answers.
A full assay will tell the whole story.
Thank you very much
Before i cement out
the solution with copper
I do test the solution with Stannous chloride
and it was black and bit purpple
But as I'm new in refining
I was with lot of doubt and I choose to cement out to see what i get from that solution.
I will follow your advice
and redisolve it and check again with stannous again.

Thank you very much
 
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Thank you very much
Before i cement out
the solution with copper
I do test the solution with Stannous chloride
and it was black and bit purpple
But as I'm new in refining
I was with lot of doubt and I choose to cement out to see what i get from that solution.
I will follow your advice
and redisolve it and check again with stannous again.

Thank you very much
You may need to dilute it, if it is very black. The colour should be purple for gold and orange for Pt.
Pd gives a greenish mixed colour.
If it is a mix you may get strange results color wise.
You could then drop the gold with SMB and test again without the gold.
 
You may need to dilute it, if it is very black. The colour should be purple for gold and orange for Pt.
Pd gives a greenish mixed colour.
If it is a mix you may get strange results color wise.
You could then drop the gold with SMB and test again without the gold.
Thank you very much
You help me a lot
I will do it.
Thank you
 
Thank you very much
You help me a lot
I will do it.
Thank you
After the cementation is done, don´t forget to brush that copper pipe - some values tend to stick to the surface and they don´t fall off on their own, or with just rinsing.

Be aware that in mining waste solutions, mercury and arsenic could be present as well - and these are severly toxic. If you immerse copper pipe to the solution, mercury will precipitate from the solution together with other values.
If you aren´t sure, never smelt the cemented metals. Rather dissolve them again in AR and proceed from there. By doing this, you circumvent possible mercury volatilization during heating and smelting.

Stay safe
 
After the cementation is done, don´t forget to brush that copper pipe - some values tend to stick to the surface and they don´t fall off on their own, or with just rinsing.

Be aware that in mining waste solutions, mercury and arsenic could be present as well - and these are severly toxic. If you immerse copper pipe to the solution, mercury will precipitate from the solution together with other values.
If you aren´t sure, never smelt the cemented metals. Rather dissolve them again in AR and proceed from there. By doing this, you circumvent possible mercury volatilization during heating and smelting.

Stay safe
Thank you for the advice

let me tell you the process that i was doing and the ore that i was use it.
and let see what you guys are thinking about

I was use a very rusty Rhyolite
i pulvurize and put the material in a beaker with sulfurix acid and a bit of distiled water
heated but not boiled for 40 minutes
in open air outside my home
let cool down,decanted the solution
washed the material several times
them i put aqua regia
with little nitric acid enought for the process
and few drop of sulfuric acid
them heated but not boiled for 1 Hour

let it cools down and cotton filter
twice
after that i separate it in two parts

i put one part with the copper pipe and the other part
i save it until i know i good process to get the value of it.

i apologize for english
i still learning
 
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Why do you choose to process it like this ?

If anything of value go into the AR solution, you will cement it all out on copper. In terms of reducing volumes of liquid to just handful of concentrate, this is the best recovery method - widely applicable and nearly 100% effective. Just need to be in the solution for quite a time, and solution should be agitated for better circulation of liquid inside the vessel.
 
Why do you choose to process it like this ?

If anything of value go into the AR solution, you will cement it all out on copper. In terms of reducing volumes of liquid to just handful of concentrate, this is the best recovery method - widely applicable and nearly 100% effective. Just need to be in the solution for quite a time, and solution should be agitated for better circulation of liquid inside the vessel.
Thank you for the advice

Because of my lack of knowledge
working with aqua regia.

if get anything of value
i trying to make it the best way possible to leach the gold out off the gold ore.

I was thinking that heat the ore with concentrated sulfuric acid solution
will i get rid of most base metal
and aqua regia with dissolve of others precious metal that could be in the ore.

I think leaching gold from gold ore this way more faster
than Chlorination of SSN.

if i learn how to do it the right way.
and if i can possible keep the consumption of nitric acid to a minimum.
can be profitable.
maybe I'm wrong
for reason i want to hear from peoples with more knowledge and learn from them.
 
Sulfuric acid helps you to get rid of basic carbonate minerals (if there are any), and also some oxides to some extent. Remember that you do not have metals in there, there are metallic compounds. It is very different to take copper or iron and dissolve them in acid, than taking malachite or hematite and dissolve them in acid.

Actually, you maybe done good with sulfuric acid. There are some cases when you cannot perform acidic pre-leach with aggresive strong acid like HCl. Many ores contain pyrolusite or burel - manganese dioxide. If MnO2 is present and you pour HCl into it, it reacts and generate chlorine. That will slowly dissolve the gold.

Other big question is.. If the gold is naked to acid leach solution. If it is liberated or enclosed still in the rock. Did you panned some of the crushed material and seen gold ? Or the gold is invisible and you try to prove it is there ?

My assumptions:
There are far better methods how to analyse and process the ore like you are describing. Rusty means lots of oidized iron in oxohydroxide form. That need acid to be converted to ton of liquid Fe waste - ineffective.

Be sure that ore do not contain sulfides. Pouring acids on sulfides isn´t good idea. Sulfides are reducing agents - altough not that reactive, they can slowly react and depleting your AR solution from nitric acid oxidizer - or dropping your gold back to solution. If the sulfides are concerned, I will firstly roast the ore to get rid of them.

Finally. If you are trying to chase the values in some type of deposit, firstly, you must be sure they are there. It isn´t an very big deal to take represenatative sample from outcropping and pay for one analysis to be sure your values are there. Then I will start to elaborate recovery process.
 
Thank you guys for the advice
I will be very carefull when dealing with some kind of ore with arsenopyrite.

the ore that I took
is an example for a old abandoned mine with free mill gold
it was just 5 lbs of ore.

in this case it's appears that it have invisible gold
because when i crushed and panned
i don't see any visible gold
not even with a loop

the history of that mine is not to extensive ,but is for gold and silver as well.

it have tons of high grade ore just outside in a pile that the miner left it
long time ago

i roasted ore to dead roast for almost 1.5 hrs
after that i do the pre leach process with sulfuric acid
and then AR.

I have some knowledge with SSN
and cement out with Zinc powder
and i get very good result
but that process is way longer
if I learn this new way working with AR
and if a get values of it.
can be profitable

this sunday I will dissolve the sludge with AR as you Guys told me to do

thank you for the valuable advice
learning is a process
and thank you for sharing your knowledge.
 
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Hello guys
I pick the black sludge ,that i get from the copper cement out and I heat it with dilute it nitric acid
and this is what i get.

when from black powder 1 picture
to the light color in the 2 picture.

I have no idea what happen
I think is not brown compare to others pictures of gold precipitation that others peoples get.
 

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Hello guys
I pick the black sludge ,that i get from the copper cement out and I heat it with dilute it nitric acid
and this is what i get.

when from black powder 1 picture
to the light color in the 2 picture.

I have no idea what happen
I think is not brown compare to others pictures of gold precipitation that others peoples get.
Looking at the hairs in your pm cement, I suspect you did not filter before cementing.
Making it organic chemistry which i can't help you with.
So anything could have happened.
Junk in junk out.
Something reacted with your cement possibly forming nitrates. It's not silver, that should have dissolved.

Ore can contain mercury and tungsten which are less rective than copper and can also cement out on copper. (I think, and needs confirmation)

Is there any brown powder left on the bottom?

Maybe dissolve a small sample in AR and test with stannous for pm's.

Martijn.
 
Thank you the reply

I agree with you,i guess is pure junk
I just put it a side and I will start
again
I learn from the advice giving to me here
and from all this mistake that a make.

I really don't see any brown powder
in the beaker.

i have another part of the same solution and i do stannous test
and this is what i get
 

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It may just be the picture or my screen, but to me that looks brown. It is what we refer to as a false positive. Gold will be a definite purple. If there is a lot of gold in solution, the purple can be so dark it looks black.

Dave
 
Thank you Dave
Yes it was very black and brown
I cemment out the solution with zinc
and i wash it the zinc precipitate with nitric acid and heat it.

and the solution getting light blue
could be silver?
 

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