# Is silver actually used for coating copper wire?

I heard stranded copper wire would be silver-coated for better conductivity at high frequencies (skin effect). But silver is at least an order of magnitude more expensive than copper, yet only has 5% more conductivity. Is silver actually used for this?

• I dunno about silver-plating, but litz wire is definitely a thing, and that is much more costly than silver-plating would be. – The Photon Aug 6 '13 at 16:32

Yes. Silver Plating is a commonly used plating material for conductivity. (There is also some debate whether silver helps in preventing tarnish or corrosion compared to bare copper, see this NASA Research PDF). Silver by the pound is more expensive than Copper (~20 dollars for one ounce of silver to ~19 cents for an ounce of copper), but we are talking about plating. A very very thin layer of electro-chemically adhered silver is very cheap in comparison to a single strand of copper wire. Typical plating thickness is just 2µm or greater. The same is done with tin or nickel or gold (Gold being ~1,283 DOLLARS PER OUNCE)

• @Johan.A the mentioning of gold is an example of a high cost material being used as plating. Gold being (today) $1283 to Silver's$19.55 to Copper's ¢19 per ounce. It's mentioned to show that yes, they are typically used, and how they are used (very thin electrochemically added layers) in comparison to copper (1 ounce of silver will cover many many pounds of copper). – Passerby Aug 6 '13 at 17:02