When 18 KT GE is inscribed on a ring, it means that the ring is an 18 karat gold electroplate. Electroplate refers to a thin layer of gold, at least 7 millionths of an inch, that is bonded to a base metal, commonly brass.
During the electroplating process, gold and a base metal are immersed in a conductive liquid and an electric current is applied that breaks down the gold and adheres it to the base metal, creating a durable bond. Heavy gold electroplate refers to gold plating of 100 millionths of an inch or more and is stamped HGE. Eighteen karat gold is 75 percent gold and 25 percent alloy.