Acid Solutions to test silver

[Pete]

I watched Youtube videos of testing silver using acids.

 

Some of the tests should only be applied to scrap coins and bars as the acid will permanently damage the surface.

There are acid solutions containing ingredients that make testing very simple - like red is silver, green is xyz and blue is pqr and so forth.

I searched around a bit and ended up buying a 10mL "professional" solution from a "reputable" UK supplier only to find it doesn't work per the videos. Guess I bought the wrong stuff assuming "professional silver solution" would be a higher quality / better choice than the cheaper stuff.

It cost about £10 for a few drops so hellish expensive for nitric acid - someone is laughing out loud !

 

Has anyone used acid solutions and how did you get on ?