- Gold plated jewelry has a fine layer of gold coated to the outside of a metal base (often nickel). The gold layer must have a minimum thickness of .5 microns.
- Gold electroplated jewelry has a fine layer of gold coated to the outside of a metal base (often nickel). The gold layer must have a minimum thickness of .175 microns.
- Gold filled jewelry is created by using heat and pressure to permanently fuse a layer of gold over a metal base. The minimum layer of gold must equal 1/20th of the total weight of the finished item. An item stamped with "1/20 14k GF" means 1/20th of its total weight is 14 karat gold.
- Rolled gold plate is similar to gold filled, but the quantity of karat gold is less than 1/20th of the total weight of the finished metal piece. An item stamped with "1/40 14k R.G.P." means 1/40th of its total weight is 14 karat gold.
- Heavy gold electroplated jewelry has a thick layer of gold coated to the outside of a metal base (often nickel). The gold layer must have a minimum thickness of 2.5 microns (100 millionths of an inch).
- Gold vermeil jewelry has a thick gold layer over sterling silver with a minimum thickness of 2.5 microns (100 millionths of an inch).
I prefer vermeil: it's much more affordable than solid gold made completely with precious metals.
What about those karats and colors?
24 karat gold is solid gold, with no added metals. It's too soft for most jewelry, so the gold is mixed with other metals like nickel or zinc for hardness. The number of karats tells you what fraction of gold was used in creating the metal of your piece. For example, 14 karat gold is made of 14 parts of gold and 10 parts other metals. Copper is added to create rose gold, silver to create green gold, and nickel or palladium are added to create white gold. Much of the white gold being produced in the U.S. is also plated with a thin layer of rhodium to give a brighter white color.
