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Fuzzy pennies are bad for the grade

2003

Hi,

I am a junior in high school, and for one of our(myself and a partner) science projects we have chosen and made *some* headway with is electroplating. We have been trying to silver plate a penny using silver nitrate(no cyanide here, that is some nasty stuff) and have attempted this several times, however we have the same lousy outcome no matter what we tweak with. The penny always turns black and then the silver starts forming black crystals on the penny and look fuzzy, if it gets thick enough on the penny the fuzz turns a bit grey, but obviously far short of actual plating. We have contacted a chemist who does electroplating for his job and he said that our setup and method was correct, but the nitrate from the silver nitrate was the root of the fuzz problem, I can't figure out how that works, why it messes up out attempts, and how, if at all, this can be fixed.

Thank you for your time, and your site has been quite useful for other methods of doing this and similar things, if we can't get the silver to pan out, we will switch to copper plating a nickel, and please do not go straight to "do the nickel," our teacher is quite excited by the prospect of success and we don't want to switch if it can be avoided.

Adam F
- Santa Barbara, California, USA

Adam, there is no commercial way to plate silver from a silver nitrate solution. One major problem is that it is photoreactive. It turns black in light. You could spend a lifetime finding the precise pH and organic modifier that would allow you to get a non shiney semi smooth plate from silver nitrate. What you got is exactly why it is not used. Alternative-Contact Technik and see if you can buy a very small amount of their Cy-less silver solution with operating instructions. This is a pyrophosphate based plating solution-NO cyanide. There is at least one other company that has a similar formulation. Hit a major college library and you can search patents and other references on the internet for homemade formulations that will work, but not well. Do not be surprised if no one will sell you or your teacher plating chemicals. They are not in the tiny chemical market and there is a huge liability for them.

James Watts
- Navarre, Florida
2003