Gold fill over Brass

[Yggdrasil]

They dont look like formal shells of themselves as there were 4 pieces of jewelry.

Just an idea.
How do you make your AR?

 

[dofustofy]

You are double quoting so to whom is the question directed?
If it was me I wondered if you expected the foils to be intact after AR.

This phrase do hint at that:

I know the foils will not be intact after AR at that point everything will go into solution.

 

[Yggdrasil]

I know the foils will not be intact after AR at that point everything will go into solution.

Yes but how do you make your AR?

 

[dofustofy]

Just an idea.
How do you make your AR?

a mixture of three parts concentrated hydrochloric acid one part nitric acid

 

[Yggdrasil]

a mixture of three parts concentrated hydrochloric acid one part nitric acid

Aah, then we have solved the issue.
That is way to much Nitric.
Cover the foils in HCl (any strength), then add Nitric in small amounts by pipette until the Gold is dissolved.
Even better if you can heat it, preferably to appr 70 Centigrade.
For this much foils I'll guess 1-2 ml will be enough.

You should read the links I gave you and in particular Hokes book.
It is old so some practices have changed a bit, among that how we use AR.

 

[Yggdrasil]

a mixture of three parts concentrated hydrochloric acid one part nitric acid

These foils will probably dissolve in HCl/Bleach or HCl/Peroxide very well too.

 

[Martijn]

Yes, that is correct. If you look closely at the screenshots I uploaded you can see the test sample has some odd precipitate form at the bottom of the beaker.

That green solution may still hold gold looking at the yellow at the edges. Did you test a drop with stannous?
Edited to say: nevermind. Yggdrasil found the issue.

Stop for a while and start reading. Then ask before you proceed.

 

[dofustofy]

Most likely too much Nitric.

Lets assume for a moment there is to much nitric can I use sufamic acid to reduce the nitric acid? I was sure to boil off all the excess nitric but, maybe not. On the small amount I have in my test beaker I just added SMB and I noticed nitric oxide fumes coming from the reaction.

 

[dofustofy]

These foils will probably dissolve in HCl/Bleach or HCl/Peroxide very well too.

I agree I am going to try another test batch using HCI / Bleach method. Thank you for the suggestion

 

[dofustofy]

That green solution may still hold gold looking at the yellow at the edges. Did you test a drop with stannous?
Edited to say: nevermind. Yggdrasil found the issue.

Stop for a while and start reading. Then ask before you proceed.

No. I did no test drop. I will need to order more stannous.

 

[dofustofy]

I just wanted to show you guys what sits at the bottom of my test beaker after I drop using sodium metabisulfite. That doesn't look like Gold. Plus there was no color change as expected using SMB. Anywho, I just wanted to share with you guys. Thanks for all you guys help and advise.

 

[Yggdrasil]

Lets assume for a moment there is to much nitric can I use sufamic acid to reduce the nitric acid? I was sure to boil off all the excess nitric but, maybe not. On the small amount I have in my test beaker I just added SMB and I noticed nitric oxide fumes coming from the reaction.

The brown smoke is because the Gold drops and redissolves immideately.

 

[Yggdrasil]

No. I did no test drop. I will need to order more stannous.

Find some solder and dissolve it in HCl. Easy and cheap.

 

[Shark]

I just wanted to show you guys what sits at the bottom of my test beaker after I drop using sodium metabisulfite. That doesn't look like Gold. Plus there was no color change as expected using SMB. Anywho, I just wanted to share with you guys. Thanks for all you guys help and advise.

How much SMB have you used in this solution?

 

[dofustofy]

Can you confirm.
Is it Gold filled or Gold plated?
There is a major difference.

Gold fill

 

[dofustofy]

How much SMB have you used in this solution?

I used more than I should had. But, I slowly dropped SMB into the solution and the reaction started to put off very little nitric oxide fumes. I continued to slowly add thinking I had to much nitric however there was no color change that typically happens when I drop my gold bearing solutions using SMB. The color stayed dark green and after a bit that white salt looking precipitate formed at the bottom of the beaker.

 

[dofustofy]

I used more than I should had. But, I slowly dropped SMB into the solution and the reaction started to put off very little nitric oxide fumes. I continued to slowly add thinking I had to much nitric however there was no color change that typically happens when I drop my gold bearing solutions using SMB. The color stayed dark green and after a bit that white salt looking precipitate formed at the bottom of the beaker.

I thought it might had been to much SMB myself but no I dont think that is it

 

[dofustofy]

The brown smoke is because the Gold drops and redissolves immideately.

Ok, update. The hydrochloric acid and Bleach method you mentioned worked. The Gold dropped outta solution using SMB this time.

 

[dofustofy]

I agree I am going to try another test batch using HCI / Bleach method. Thank you for the suggestion

Ok Update. The HCI / Bleach method worked.

 

[dofustofy]

Update, the HCI / Bleach method worked on this Gold fill over brass jewelry.