Chrome plating, a technique of electroplating a thin layer of chromium onto a metal or plastic object, can be decorative, provide corrosion resistance, ease cleaning procedures, or increase surface hardness.

Nickel is a silver white, hard metal with satin to bright luster. It can be plated uniformly in recesses, blind holes and cavities, does not build up on edges.
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Passivation of stainless steel is not electroplating, it is a non electrical process that removes surface impurities that cause corrosion and promote friction-related damage in stainless steel.
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Phosphate coating, a chemical conversion coating that transforms the surface of a base metal into a non-metallic crystalline coating.

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Silver, being the least expensive precious metal, is the first option when considering the use of a precious metal.

Tin plating is commonly used to protect surfaces. Tin has several alloys that are employed regularly in the tin electroplating process. 

Zinc plating is a soft, ductile, decorative, marginally solderable, corrosion-resistant finish. 
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