Rolled Gold, Gold Filled and Plated: Reading the Marks on the Layer
Between solid gold and gilt brass lie four or five distinct constructions, each with its own marks and its own lifespan. The difference between a piece that will outlive you and one that wears through in a year is a number stamped in the clasp.
Updated 2026-08-04·4 min read
Gold over base metal is not one thing. It is a family of constructions that differ by a factor of a hundred in how much gold they actually contain, and the trade marked them with reasonable honesty, which means the answer is usually stamped on the piece. Learning the marks takes ten minutes and settles most of the questions people ask about inherited jewelry.
Fig. 01 The same question in cross-section. Thickness is drawn to a logarithmic scale, since a plated micron and a gold filled layer cannot be shown truthfully on the same linear ruler.