Precipitating gold..

[Renstilsken]

Hello forum how has the new year been treating everyone .. good I hope.
Well let me get into into it.. I had a 14k. Chain that weighed 60 grams , so I melted it down and added another 30grams of pure silver . And then put it in nitride acid, after the silver went into solution. I then risnsed it and then put into Aquila regalia . And it went into solution. , which was a slight yellow green color. After that I then added urea. To take acid out. And after that I added sodium metabisultie too.. so here is my issue.. the solution turned red color.. but no gold dropped out.. where did I go wrong.. please help.. thanks any and all input.

 

[anachronism]

OK firstly.

It's Nitric Acid.
It's Sodium Metabisulphite.
It's Aqua Regia.

Not the silly names you are posting up here please be accurate in your descriptions, and you have been asked to do this before.

Now. Before we can help: How much HCl, how much Nitric please?

Edit: Was it a 14 karat plated chain or a solid 14 karat?

 

[Renstilsken]

14 karat solid gold chain. And I started with 100 mili liters of Hcl, then added nitric as needed until it all desolve. I add nitric increaments of 10 milliliter at a time . So..40 milk liters. Sorry for the mis spelling.

 

[anachronism]

Ok well that's good then. You've therefore got at most 10ml of Nitric to remove.

Personally I don't think you have removed all the Nitric. Urea isn't the preferred way to get rid of Nitric but did you add it in increments until there was no further reaction or did you add a bit then assume the Nitric would be removed?

Edit: When you added the SMB did you get a reaction or did it just go to the bottom and sit there? I ask because the SMB requires an acidic solution to gas off the SO2 to precipitate the gold.

 

[Renstilsken]

No I did not get a response.. it just drop to bottom and solution turned red..what can I do to fix this ..please..

 

[anachronism]

I'm sorry but it is later here and I have to go to bed but here are a couple of pointers.

If you have neutralised all the Nitric it's possible that you have also turned the solution into a base solution with the Urea in which case you will need to reacidify it with some additional HCl. Then your SMB will work and drop the gold.

Try an additional 15ml of HCL and see what happens.

 

[Renstilsken]

Thanks so much for the pointer I will give it a try thanks.