Gold vermeil jewelry is sterling silver that has been coated with a thin layer of gold through a process called electroplating. Many countries have strict regulations over what constitutes gold vermeil jewelry. In the US, in order for a piece to be considered gold vermeil, the gold must be at least 2.5 microns thick and be at least 10-karat gold.  Gold-filled jewelry has either sterling silver or brass base with a gold coating. Electroplating or heat pressure is used to bind the base to the gold. Gold-filled jewelry is considered more durable for everyday use. Gold-filled jewelry is waterproof and an excellent choice for those wanting quality gold without having to pay a high price. Gold-filled pieces will have a GF stamp on the clasp or somewhere hidden on the jewelry. Gold-plated jewelry has the thinnest layer of gold surrounding the base metal. In fact, gold-plated pieces have .05% gold alloy, while gold-filled jewelry has 5% gold alloy thickness. While gold-plated jewelry is great for costume jewelry, I recommend buying gold-filled or gold vermeil, if not solid gold and sterling silver, for your most worn pieces.