Gold-filled jewellery became popular in the early 20th century and increased in use throughout the 1930s and 1940s. Gold filled is a far better alternative to gold plated, due to its durability.
Gold-filled wire is made by bonding a layer of 10-karat, 12-karat or 14-karat gold to a base of sterling silver or jeweller’s brass. The wire is then drawn to the desired thickness. The final layer of gold is 5 – 10 times that of regular gold plating and up to 25 times that of gold electroplate. The gold layer is typically at least 5% of the items weight.
Most high quality gold-filled pieces have the same appearance as high carat gold, and gold-filled items, even with daily wear, can last 10 to 30 years.
Please note that gold filled jewellery can tarnish under certain circumstances. There are a number of reasons why it can tarnish, but for the vast majority of us, other than normal soiling, gold-filled jewellery will retain its beautiful gold appearance for many years.