Gold-filled can last between 10 to 30 years, but will eventually wear through. Gold-filled items are 5 to 10 times thicker than regular gold plating, and 15 to 25 times thicker than gold electroplate.
Gold-filled jewelry is composed of a solid layer of gold and is then bonded to a base of either a base metal or some sort of sterling silver.
Gold plating is a method of depositing a thin layer of gold onto the surface of another metal, most often copper or silver. It is electroplated.