Q&A on Silver plating of flatware, serving platters, etc.

A. Hi Rinku. We've added your question to a thread where Chris Owen has answered it quite authoritatively :-)

You might also want to get access to the book he mentions.

Luck & Regards,

A. Hi Ali. We'll see if Chris' e-mail still works and if he's available to offer help 5 years later. But if by "micron plating" you mean plating of 1 micron thickness, you will see from Chris' post that even "half plate" is nearly 4X that thick; so it's hard to expect micron plating to survive long in a restaurant.

Chromate is toxic and must not be applied to food-service items, but there may well be food-safe clear coats that can improve the tarnish resistance and prolong the life of your silver (although some people claim, perhaps rightfully, that no coating is really acceptable on the silver plating of food-service items.

Luck & Regards,

A. Hi, Earl.

Well over 90 percent of all silver plating is done from cyanide baths, and this has been the case for a hundred years. As long as you are certain that the flatware is well rinsed, and has no capacity to trap the solution, there is no danger to the consumer (although cyanide is obviously dangerous to your employees).

Strong and toxic chemicals are often needed to make food-safe materials. Stainless steel flatware is often treated with hazardous nitric and hydrofluoric acids, so it's not a matter of silverware being more dangerous than other flatware.

I'm not sure that I understand why either the acid copper or the nickel plating is required for flatware. If you wanted bright and shiny silver plated platters, that would probably be different.

Regards,

A. I have a copy of a quite authoritative book, "Silver: Economics, Metallurgy, and Use", by Butts and Coxe, written in 1975 and sponsored by Handy and Harmon. It lists 6 thickness categories of silver plating to be used on flatware (page 188). The lowest thickness is 3.75 microns and is called "Half-Plate." The greatest thickness listed is 33.75 microns and is called "Federal Specification Plate." There are 4 others in between these two. A typical application of the thicker plating categories would be in hotels.

Some of these specifications call for extra plating on the wear surfaces - i.e., the backs of the spoons and the tines of the forks. For example, on the Federal Spec Plate mentioned above, the thickness in those wear areas should be a minimum of 45 microns.

The six categories in terms of silver thickness, in microns:

Half-Plate = 3.75
Standard Plate = 7.50
Double Plate = 15.0
Triple Plate = 22.5
Quadruple Plate = 30.0
Federal Spec. Plate = 33.75

I might note that the Federal Spec Plate is 1 troy ounce (31.1g) of silver per square foot (10.8 dm2) of surface area.

As far as answering your question, I have no idea as to what thickness you should use. It all depends on the amount of usage and wear these objects will be subjected to. These figures surprised me also. However, it is obvious that pure silver is a soft metal that wears, especially when polished.

I have seen silver plated flatware stamped with some of these designations, such as "Standard Plate." I would think that, in the US, if you wanted to stamp these designations on the flatware, you would have to adhere to the appropriate thickness requirements.