UK Gold Hallmarks Identification Guide

The 3 Compulsory UK Hallmark Stamps

Under the UK Hallmarking Act 1973, all gold items sold in the UK weighing over 1 gram must carry three compulsory marks:

1. Sponsor's Mark (Maker's Initials): Unique initials representing the goldsmith or manufacturer inside a shield shape.
2. Milliesimal Fineness Mark: 3-digit number inside an oval shield indicating pure gold content per thousand (e.g. 375 for 9ct, 750 for 18ct).
3. Assay Office Mark: Indicates which official UK Assay Office tested the metal:
   • Leopard's Head: London Assay Office
   • Anchor: Birmingham Assay Office
   • Rose: Sheffield Assay Office
   • Castle: Edinburgh Assay Office