Our Hallmarks & Hallmarking

A hallmark records an independent test of precious-metal fineness. Roberts & Co uses the Goldsmiths’ Company Assay Office in London. Hallmarking details vary by piece; refer to the individual product description and photographs.

Reading a UK hallmark

• Sponsor’s mark: identifies the registered person or company responsible for submitting the article. It does not, by itself, identify who manufactured it.
• Fineness mark: states the precious-metal content in parts per thousand.
• Assay Office mark: identifies the office that tested and marked the article. London uses a leopard’s head.

These are the three compulsory components of a standard UK hallmark. A date letter and traditional fineness symbol are optional additions. The lion passant is the traditional symbol for sterling silver.

A 925 stamp is not a full hallmark

Sterling silver contains 925 parts of silver per thousand. A numerical 925 stamp alone is not the same as an independently applied UK hallmark.

Small pieces and weight exemptions

Silver articles below 7.78g and gold articles below 1g are exempt from compulsory hallmarking on weight grounds. An exempt piece must still match its description. Other exemptions and rules can apply; the London Assay Office’s guidance explains these in more detail.

Materials and finishes

A gold-plated silver piece remains silver beneath its finish. Read the product’s metal and finish information alongside its marks. Our Materials & Hallmarking guide explains sterling silver, solid gold and gold plating.

For illustrated examples, visit the Goldsmiths’ Company Assay Office hallmark guide. For a question about a Roberts & Co piece, contact us.