The difference between gold filled and gold-plated ring guards
Gold Plated is a layer of gold-plated to a base metal such as brass (usually via electroplating). This is usually a very thin layer, which is likely to wear quickly and is easy to scratch. The gold film also naturally wears thin with time,
due to rubbing and exposure to skin salts, exposing the metal below. Gold plated can have the look of karat gold but is not recommended for constant wear.
Gold Filled has approx 100 times more gold than plated. The technique of mechanically bonded layers of gold and a base metal is used. Gold filled looks and usually wears as well as karat gold, and should last under normal wear conditions, for a lifetime. Our ring guards are 14k gold filled and the gold will not thin with constant wear, or if worn in water.
Here is more on Gold Jewelry you may find interesting:
http://jewelry.about.com/od/jewelrymetals/a/gold_jewelry.htm