The Real Gem Guide to Hallmarking
Authenticity You Can Trust
Every gold and platinum piece from The Real Gem is independently hallmarked in line with UK law: your assurance of the metal's purity.
What Is a Hallmark?
A hallmark is an official mark stamped onto precious metal to confirm its purity. In the UK it's a legal requirement for gold, silver, platinum and palladium items above a certain weight.
Hallmarks are applied by an independent Assay Office, which tests the metal and confirms it meets the standards set by the Hallmarking Act 1973.
Good to know: a hallmark is more than a stamp. It's independent proof that your piece is real precious metal.
What a Hallmark Includes
Every UK hallmark has three compulsory marks, plus an optional date letter:
| Mark | Meaning | Example |
|---|---|---|
| Sponsor's mark | Identifies the maker or company responsible for the piece | Initials inside a shield |
| Fineness mark | Confirms the metal and its purity | 750 for 18k gold, 950 for platinum |
| Assay Office mark | Shows which UK Assay Office tested and marked it | London, Birmingham, Sheffield or Edinburgh |
| Date letter (optional) | Shows the year it was hallmarked | A letter that changes each year |
The UK Assay Offices
All UK hallmarking is carried out by one of four Assay Offices, each with its own symbol:
- London: the leopard's head
- Birmingham: the anchor
- Sheffield: the rose
- Edinburgh: the castle
Your Real Gem piece will carry one of these symbols, confirming it has been independently tested.
Why Hallmarking Matters
- Authenticity: proves your jewellery is real precious metal
- Purity: confirms the exact standard, such as 9k, 14k, 18k or platinum 950
- Confidence: you know exactly what you're buying
- Protection: a legal safeguard for you as a customer
Common Fineness Marks
| Metal | Mark | Typical use |
|---|---|---|
| 9k gold | 375 | Everyday fine jewellery |
| 14k gold | 585 | Mid-range fine jewellery |
| 18k gold | 750 | Luxury fine jewellery |
| Platinum | 950 | Premium and engagement pieces |
Our jewellery is made in 18k gold or platinum 950 as standard. See our Guide to Precious Metals.
Finding Your Hallmark
Look for tiny stamped symbols inside the band of a ring, on the back of a pendant, or near the clasp of a bracelet or chain. If you're unsure, contact us and we'll help you identify it.