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 Back Types of MetalsMetal FinishesHallmarking | What is a Hallmark?Ring Profiles and WeightsThe Difference Between White Gold & Platinum

Hallmarking | What is a Hallmark?

A Hallmark is a small marking that is stamped onto a precious metal to guarantee that it conforms to standards of purity and has been independently tested.

 

It is impossible to verify the precious metal content of a piece of jewellery by merely looking at it by sight or by touch. It is therefore a legal requirement that items made from platinum, gold, palladium or silver much be independently tested and then hallmarked in order to be described as such.

Fineness of Our Metals

18ct Gold (750)

75% Pure

9ct Gold (375)

37.5% Pure

Platinum (950)

95% Pure

All Purely Diamonds rings and jewellery are hallmarked at British Assay offices ensuring our precious metal jewellery is compliant with the UK’s hallmarking regulations. All items are subject to an internal confirmation process to ensure they meet the UK’s hallmarking regulations before they are dispatched to our customers.

 

We are an Assay Assured Jewellery Retailer. Assay Assured status is only given to retailers who have been independently audited and verified by Assay Assured which is run and overseen by the Edinburgh Assay Office, and ensures that all precious metal jewellery (except items exempt by weight) are independently tested and hallmarked.

Here is what to expect to see inside your Purely Diamonds jewellery

Sponsor's Mark

The registered mark of the article for hallmarking.

The sponsor’s mark for Purely Diamonds is “ST” after our company founder, Stephen Tyler.

Gold Fineness Mark

Tells you the precious metal content expressed in parts per thousand.

750 represents 18ct gold and 375 represents 9ct gold.

Platinum Fineness Mark

Assay Office Mark

This mark denotes which Assay Office has hallmarked your piece of jewellery; London, Birmingham, Sheffield or Edinburgh respectively.

These are the additional marks that may appear:

Traditional Fineness Mark

The traditional mark sees gold represented by the crown and platinum by the orb.

Date Letter

The date letter on a hallmark shows the year in which your jewellery was assayed. Each year is represented by a different letter in a set sequence. In the current cycle, the letter for 2025 is A, with B representing 2026 and C for 2027.

For full information regarding hallmark options please download the Assay Office dealer’s guide.

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Here you will find expert articles on hallmarks, finishes and the qualities of different metals, giving you the knowledge to choose jewellery with confidence.
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