Is my acid test no good?

[bpcp7208]

I have some gold that has nickel in it. I haven't refined it yet until I feel confident with my setup and knowledge to do so safely and effectively. I decided to melt a button and test it cause I was curious. Now I know by the color that it's not that pure. None of my acid tests are disappearing. I let them sit for 5 minutes before I took the picture. I just got the acid tests in the mail a few days ago. I'm assuming they have a shelf life. Does this mean it's expired?

 

[butcher]

As soon as you mix up aqua regia it starts depleting or losing strength.

The aqua regia gold test solutions are just different concentrations of these acids and will have a fairly short shelf life.

You can mix up your own test solutions as long as you have the reagents.


Nitric acid alone on the metal alloy scratch on the stone will normally tell you what you are looking for, as it will dissolve the base metal from the mark, leaving traces of gold in the scratch.

 

[Martijn]

Strange... You should get a reaction with 22K imo. A touch stone is often used with a known karat gold streak next to you test streak to compare and dilute the drops once the difference is the most obvious. This would also tell you if your test acid is good or not.

If you don't have a reference piece of gold, see if the acid dissolves a copper streak?
Nickel should dissolve in AR. Not sure how an alloy of gold and nickel reacts.

 

[nickvc]

Looking at the color of your bar I’d suggest a drop of nitric and see what reaction you get.