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Did you know? We can hallmark articles of jewellery containing both precious metal and base metal or other materials

Published: 8th April 2019


Since 2007, hallmarking legislation has allowed mixed metal items subject to the following conditions:

A mixed precious metal and base metal article, or an article of mixed precious metal and other materials, can only be hallmarked if any precious metal component is at least the minimum legal fineness for that metal i.e. silver 800, palladium 500, gold 375, platinum 850 (parts per thousand).

If an article includes base metal parts then:

 Those base metal parts must be clearly distinguishable from precious metal parts by colour and/or texture and must be clearly visible by their extent.

 The word + METAL must be applied next to the Hallmark on the precious metal part.

 Whenever practical the word METAL or the name of the metal should also be struck on the base metal part/s (brass, stainless steel, titanium etc.), in a manner which complies with any Regulation made by The British Hallmarking Council.

 The Hallmark can only be applied to the precious metal component. Sufficient space must also be available adjacent to the Hallmark for the addition of the “+METAL” mark. 

If an article does not include base metal parts, but other materials, then:

 The other materials must be clearly distinguishable from any precious metal part.

 The non-precious metal part must not be plated to resemble any precious metal.

 The extent of each part must be clearly visible.

 The precious metal part must be of a thickness of not less than 100 micrometres.

 A mixed material article containing only a single precious metal will behallmarked on the precious metal part only, as if it was a separate article.

 For an article with more than one precious metal and a base metal the rules which apply to hallmarking Mixed Precious Metals apply.

To find out more about the whole range of Hallmarking Services offered by Sheffield Assay Office, please email us at or complete the contact form on our website at

The Sheffield Assay Office was established in 1773, under an Act of Parliament and today the company assays and hallmarks the precious metals - silver, gold, platinum and palladium. Sheffield Assay Office is one of only four UK assay offices who all work to uphold the Hallmarking Act of 1973 and continue to ensure consumer protection for customers purchasing precious metals.

To find out more about the whole range of services offered by Sheffield Assay Office, such as our hallmarking and analytical services, please email us at or complete the contact form on our website at,

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