A ring that says “18KGE” is made of an unnamed metal that has a thin layer of 18 karat gold electroplated on it. This electroplated layer is different from other gold coverings because the gold was put on in a uniform way by electrolysis.
Federal rules say that for something to be called “gold electroplate,” the gold must be at least 10K pure and at least 7 millionths of an inch thick. Items that are thinner than this are usually labelled “layered in 14K gold,” although gold tone and gold wash are also legal terms. “HGE,” which stands for “heavy gold electroplate,” is written on things that are 100 millionths of an inch thick.