Restoring old silverplate

A. Real silver plating is done by electroplating, and almost always from a cyanide electrolyte. Cyanide is one of the most potent and fastest acting poisons ever discovered, so it's probably not safe way to electroplate it yourself, unfortunately.

A. Faith,

Mr. Mooney is correct in the sense that the best and real way to silverplate is with an electroplating process but he may have overlooked a cheaper way to do it without cyanide. I found a supplier of Jax silver plating solution [affil links] which is brushed on, allowed to dry, rinsed off and gives a reasonable silver plated finish without the need of electricity. It's an easy and inexpensive way to touch up parts.

Regards,

I find that you are correct, Mr. Fisher. Thanks!

In fact, I've since discovered there there are a number of commercial immersion silver plating solutions. They rely on the fact that silver will come out of solution in preference to exposed metal like copper and brass that is lower in nobility. Immersion plating gives only a thin coating because as soon as the surface is covered the reaction will cease. But if the item will not see too much wear, and you are willing to repeat it as needed, you and a number of other readers are reporting that it can work. There are a number of brands mentioned on these pages and we've added an FAQ, "Silver Plating at Home", that sources the Jax as well as Medallion Liquid Silver Plating Solution, Miracle Silver, Nu Silver, Quickshine, Silveron, Silver Plating Formula, Silver Secret, and The Silver Solution.

Thanks!

A. Perhaps because I am a chemist, I understand the risks and the way to safely handle toxic materials that I can state the following about silver cyanide plating solutions:
1. The cyanide is the water-soluble silver salt. What the properties of the cyanide ion versus other salts such as silver chloride or silver nitrate I do not know, but the industry standard is to use the cyanide salt. Gold plating uses the same chemistry.
2. The cyanide salts of noble metals are caustic, that is, they act like lye if they come in contact with skin or mucous membranes. For that reason, common sense says protective equipment is required such as splash goggles [on eBay or Amazon], apron [on eBay or Amazon] , latex or nitrile rubber gloves [on eBay or Amazon], and mechanical ventilation to prevent respiratory exposure. Should the liquid come in contact with the skin or eyes, a deluge eyewash or shower immediately proximate the location of the work is required. This is all OSHA-required industry standard. Why, because stuff happens and why take the risk?
3. On the positive side, the concentration of the salts in solution is usually not very high - a few percent at most. I'd be surprised to see them any higher, so the risk of receiving a lethal dose of cyanide gas is quite low, and requires the liquid come in contact with an acid.
4. Bleach will kill cyanide. That is, any aqueous cyanide spilled or residues when exposed to copious amounts of bleach with convert the cyanide to nitrogen and carbon dioxide. But, in an industrial setting, that is called treatment, with the exception of spill response, required an expensive permit to treat toxic waste.

So, the more the cyanide in volume or concentration, the larger the risk. Given those minimal requirements, silver or gold plating using cyanide can be performed safely.

A. Hi

Luck & Regards,


Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

A. Sorry folks, I am never going to concede that cyanide-based silver plating can be performed safely by a hobbyist. Although the danger of airborne cyanide gas may be small if the container is very small and it isn't acidified, the chance of accidental acidification is not remote. And the liquid contains 35-160 g/l of free potassium cyanide ... that is not trivial by anyone's calculation. A lethal dose of cyanide is 100-200 mg so, as an example, a liter/quart would contain somewhere between 1000 to 10,0000 lethal doses, and a stirring spoon accidentally put in the mouth might kill instantly. It would certainly be the rare hobbyist who has a deluge eyewash station.

Regards,

A. Hi, Peter. We are drowning in comment spam so we try not to ask for it by comparing one brand of stuff to another on this technically oriented forum ( huh? why?). But the site's supporting advertiser EPI / Electrochemical Products Inc. [a finishing.com supporting advertiser] offers non-cyanide silver plating processes. They recommend them only for electronics applications rather than jewelry and decorative applications because the color of non-cyanide silver plating is slightly off. But what Tiffany considers slightly off may well meet the standards of a hobbyist :-)
Good luck.

Regards,