Materials

925 Silver 

Sterling silver is an alloy of silver containing 92.5% by weight of silver and 7.5% by weight of other metals, usually copper. 

14K Gold-Filled 

14K gold- filled contains 5% pure gold by weight. There's a thick layer of real, solid 14K gold on the outside of a brass core. The 14K gold that is on the outside of gold- filled is the same gold as you would get from a solid 14K piece. 

Gold Filled VS Gold Plated 

Gold filled is the next level and is amazing, quality alternative to solid gold. Gold filled is an actual layer of gold pressure bonded to another metal.

Gold plating is the lower level and these items tend to tarnish and can often turn the skin green.