Dear Respected Members I have gold ore sand in Aqua regia and it shows very good gold by testing with tin chloride, then I have tried many times after making different aqua regia to precipitate by SMB or by ferrous sulfate after using Urea, but gold is not precipitating the solution become dark reddish or sometime dark black but after 30 minute the solution become yellow again with nill precipitation, please help me in this matter, Thanks and regards usmani
Gold not precipitating after showing with stannous chloride
- Thread starter M Usmani
- Start date
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Do not use Urea, use Sulfamic acid.
You have used way too much Nitric.
How do you make your AR?
Never premix AR. Add sufficient HCl to cover your item. Then add Nitric in increments until no more reaction. Then add some more HCl and repeat a couple steps, if no reaction, it is finished.
I trust you have done a proper assay.
Ore can have many deadly elements released by acids.
The best leach is determined by assay.
I trust you have done a proper assay.
Ore can have many deadly elements released by acids.
The best leach is determined by assay.
Jimdeveney
Member
How much does it cost for an analysis of materials?
Martijn
Well-known member
After watching your video;
You really need to stop everything you're doing!
Put that solution aside in a safe place, in a safe container and keep it loosly covered.
Go see a doctor and get a blood test.
Study how to handle chemicals, reactions and the toxic metals in solution!!
You just ruined your pregnant solution by adding stannous like that!
It is done with a drop of solution with a drop of stannous on a filter paper or in a spot plate.
https://goldrefiningforum.com/forums/safety.47/https://goldrefiningforum.com/threads/when-in-doubt-cement-it-out.30236/
https://goldrefiningforum.com/posts/40800/Use gloves!! Don't breathe those fumes!!
Use proper chemical beakers and a fume hood!
That gold is not worth your life and the medical bill can easily be far bigger than your gold!
Martijn.
Martijn
Well-known member
Dear Martin Thanks a lot for advise really I have to careful in future, I just want to show the stannous reaction that is why I have put too many stannous, still a good ratio of gold it is not precipitating. Anyway really thanks
Martijn
Well-known member
Reasons for gold not precipitating are usually:
1: toooo much nitric,
2: no gold in solution or
3: too little free HCl for the SMB to react with.
4: other mysterious things that can be in the mix by following bad youtube advice like urinating in your chemical cocktail or not perfoming the chemistry steps like filtering properly.
You get the best clearly readable stannous test results with a solution that's not concentrated, but diluted and letting it spread out on a paper filter tip.
Dark spots can be anything.
Now your soup looked like purplish, so i suspect some gold.
But study safety first and ask us before you go and copy another you tube disaster recipe.
Study the links I gave you and you will (should) know how to proceed.
But really: use gloves!!
To understand and help you with your specific issue a bit better: post a picture of your 'sand' please.
Stay safe.
Martijn
1: toooo much nitric,
2: no gold in solution or
3: too little free HCl for the SMB to react with.
4: other mysterious things that can be in the mix by following bad youtube advice like urinating in your chemical cocktail or not perfoming the chemistry steps like filtering properly.
You get the best clearly readable stannous test results with a solution that's not concentrated, but diluted and letting it spread out on a paper filter tip.
Dark spots can be anything.
Now your soup looked like purplish, so i suspect some gold.
But study safety first and ask us before you go and copy another you tube disaster recipe.
Study the links I gave you and you will (should) know how to proceed.
But really: use gloves!!
To understand and help you with your specific issue a bit better: post a picture of your 'sand' please.
Stay safe.
Martijn
Martijn
Well-known member
Great! But first desribe the steps you intend before making another toxic mess.
Looks just like a bag of 'mount baker mining machines' shaker table tailings.
What is the source?
Is it (maybe even chemical) waste in some way that was donated to you to process?
Have you tried (if you have access to it) milling, gravity separation and assaying the different fractions?
Or have you tried classifying and using a gold pan?
This will tell you if there is anything worth going after in the first place and where the most values are concentrated and how to recover it most cost efficiently.
If not, then processing ore or sand tailings like you have, maybe is not a profitable option for you.
Honestly, repeating AR, or anything else for that matter, many times expecting a different result is the definition of something I would not want to be accused of.
Assay about 100 or 200 grams of the concentrates and make a plan from there.
Martijn.
Looks just like a bag of 'mount baker mining machines' shaker table tailings.
What is the source?
Is it (maybe even chemical) waste in some way that was donated to you to process?
Have you tried (if you have access to it) milling, gravity separation and assaying the different fractions?
Or have you tried classifying and using a gold pan?
This will tell you if there is anything worth going after in the first place and where the most values are concentrated and how to recover it most cost efficiently.
If not, then processing ore or sand tailings like you have, maybe is not a profitable option for you.
Honestly, repeating AR, or anything else for that matter, many times expecting a different result is the definition of something I would not want to be accused of.
Assay about 100 or 200 grams of the concentrates and make a plan from there.
Martijn.
Hi, pool acid has an ingredient that keeps the Chlorine in solution so Aqua Regia made with Muriatic acid just redesolves the gold so it will not precipitate properly. Use Sodium thiosulfate to neutralise the excess Chlorine Gas still in solution . use very little as to much will redesolve the gold again .
Martijn
Well-known member
That makes no sense to me at all. Please explain.
Dear Martin Thanks for your detailed reply, the source is my friend who has a mine near river and from there I am getting sand on payments.Great! But first desribe the steps you intend before making another toxic mess.
Looks just like a bag of 'mount baker mining machines' shaker table tailings.
What is the source?
Is it (maybe even chemical) waste in some way that was donated to you to process?
Have you tried (if you have access to it) milling, gravity separation and assaying the different fractions?
Or have you tried classifying and using a gold pan?
This will tell you if there is anything worth going after in the first place and where the most values are concentrated and how to recover it most cost efficiently.
If not, then processing ore or sand tailings like you have, maybe is not a profitable option for you.
Honestly, repeating AR, or anything else for that matter, many times expecting a different result is the definition of something I would not want to be accused of.
Assay about 100 or 200 grams of the concentrates and make a plan from there.
Martijn.
yes I have installed Sluice box and shaking table for making concentrate, after making concentrate the iron particles not left the gold particles because gold particles are very very small than iron particles so iron came with gold too. So after that I have tried aqua regia method to recover gold but failed. Now with all precautionary measures I would like to make aqua regia with very less Nitric acid and would try to precipitate as per your advise, I would be thankful if you spare some time and some line to guide in this matter
thanks and regards
Martijn
Well-known member
Near a river you say. You (may) have sand containing placer gold.
Are you paying for bags of tailings or concentrates or just sand dug up and you're concentrating it? Not quite clear to me.
That assay report is from sept. 2019, describing crushed ore... now is it sand or crushed ore? Ore comes from hard rock mining, placer gold sand is classified, washed and concentrated.
Did you pay for this assay, and why wait three years before processing this ore?
Are you sure he's your friend? Friends are not always the best buisiness partners.
Sounds to me he once got a good assay and now uses that to sell river sand with magnetic black sands.
Anyway, i believe your possible gold containing sand was concentrated in the ground by river gravity separation in stead of hard rock, so It can be washed back out again.
No need for chemistry imo.
Classify better to comparable particle size and you can separate it all better.
Separate iron from gold with a magnet under water, preferably where the gold line on the shaker table starts and repeat several times on both concentrate and magnetic tailings to get a better separation each time. You will drag some gold out with the iron. So redo that a couple of times to purify the gold. Put the magnet in a bag to get the iron off easily.
Once you have clean gold concentrate, just melt into a ingot and sell it with a bit of impurities. The buyer will scan the purity and pay you accordingly.
Do you have a picture of the concentrates you processed with AR?
Why do you want to refine it further?
Assuming you've at least watched the safety lesson and have improved your safety standard:
To test for pm's with AR, dissolve a bit of the concentrate from the bottom in a test tube.
Add a bit of concentrate to a test tube, cover it in HCl and add one drop of nitric.
To speed the reaction up safely, you could au-bain-marie the test tube in hot water.
Add HNO3 one drop at a time until no more reaction is happening, so there are no more tiny bubbles forming upon addition of one drop of HNO3.
If you had to add relatively much HNO3, the reaction could be stopping because of low HCl level, adding two drops of HCL will show that.
When the reaction is done, all metals exept for silver will have dissolved, you can pick up one drop of the hopefully pregnant solution with a glass stirring rod and let it fall off in a spotplate or on a filter paper. Or dip a filter tip in the solution with a pincet, wetting only milimeters is enough.
Add one or two drops of stannous and watch if there is any purple discoloring. If its too dark to see, add a drop of water until its dilute enough to see. Only purple is gold! Brown is not.
Oh, and iron dissolved in HCl looks just like gold chloride! Nice and deep yellow color.
To make things clear: the only thing i've ever panned was gold bonding wires from 50 grams of IC chips...and made a fortune..., not! LOL
8 years GRF membership and my curiosity got me this far.
So my help regarding placer gold is purely theoretical.
But I will get corrected by other members if talk nonsense.
I'm really curious what your replies and results are.
Good luck!
Are you paying for bags of tailings or concentrates or just sand dug up and you're concentrating it? Not quite clear to me.
That assay report is from sept. 2019, describing crushed ore... now is it sand or crushed ore? Ore comes from hard rock mining, placer gold sand is classified, washed and concentrated.
Did you pay for this assay, and why wait three years before processing this ore?
Are you sure he's your friend? Friends are not always the best buisiness partners.
Sounds to me he once got a good assay and now uses that to sell river sand with magnetic black sands.
Anyway, i believe your possible gold containing sand was concentrated in the ground by river gravity separation in stead of hard rock, so It can be washed back out again.
No need for chemistry imo.
Classify better to comparable particle size and you can separate it all better.
Separate iron from gold with a magnet under water, preferably where the gold line on the shaker table starts and repeat several times on both concentrate and magnetic tailings to get a better separation each time. You will drag some gold out with the iron. So redo that a couple of times to purify the gold. Put the magnet in a bag to get the iron off easily.
Once you have clean gold concentrate, just melt into a ingot and sell it with a bit of impurities. The buyer will scan the purity and pay you accordingly.
Do you have a picture of the concentrates you processed with AR?
Why do you want to refine it further?
Assuming you've at least watched the safety lesson and have improved your safety standard:
To test for pm's with AR, dissolve a bit of the concentrate from the bottom in a test tube.
Add a bit of concentrate to a test tube, cover it in HCl and add one drop of nitric.
To speed the reaction up safely, you could au-bain-marie the test tube in hot water.
Add HNO3 one drop at a time until no more reaction is happening, so there are no more tiny bubbles forming upon addition of one drop of HNO3.
If you had to add relatively much HNO3, the reaction could be stopping because of low HCl level, adding two drops of HCL will show that.
When the reaction is done, all metals exept for silver will have dissolved, you can pick up one drop of the hopefully pregnant solution with a glass stirring rod and let it fall off in a spotplate or on a filter paper. Or dip a filter tip in the solution with a pincet, wetting only milimeters is enough.
Add one or two drops of stannous and watch if there is any purple discoloring. If its too dark to see, add a drop of water until its dilute enough to see. Only purple is gold! Brown is not.
Oh, and iron dissolved in HCl looks just like gold chloride! Nice and deep yellow color.
To make things clear: the only thing i've ever panned was gold bonding wires from 50 grams of IC chips...and made a fortune..., not! LOL
8 years GRF membership and my curiosity got me this far.
So my help regarding placer gold is purely theoretical.
But I will get corrected by other members if talk nonsense.
I'm really curious what your replies and results are.
Good luck!
Dear Martin thanks a lot for your so much detailed teaching. Actually the report is of 2019 is in detail, now we are using another lab for testing because it is cheap, I may share it too. we have given crushed sand of 200 mesh to lab so they have mentioned it ore, whereas in natural the sand size is approx 30 to 40 mesh. I am sharing concentrate lab report from other local lab.
thanks again for your reply and surely I will give you good news very soon after experiment
regards
