What does it mean when a ring is stamped, 18K GERSC ?
First, we have to examine what are the numbers and letters inscribed on the ring.
Upon searching, we found that this item is an 18 karat "Gold Electroplate" made by the R.S Covenant Jewelry (hence, the GERSC hallmark).
Electroplated gold means that the piece of jewelry is made of some less expensive material, but has a thin layer of gold on the surface.
By Federal standards, in order to be called gold electroplate (or G.E.), the gold must be at least 7 mils (millionths of an inch) of an inch thick and of a fineness of 10K or better.
The words goldtone and gold wash are Federally approved terms for items less than 7 mils, however, "layered in 14K gold" is commonly used. There is no Federal standard for the word "layered", so it can mean any thickness of gold, even as low as 1 mil.
And since it's an 18 karat GE ring, the surface is made up of 75% gold and 25% alloy (since pure gold [24K] is rarely used in jewelry because it is too soft).
Get more facts about gold at ForemostJewelry.com.
Tips! Learn Seven Ways to Tell If Your Gold Is Real, shared by Money Morning.