In this guide
Every gold ornament sold legally in India carries a set of marks so small that most buyers never look at them. Those marks are the only independent proof you have that the gold you bought is the gold you were promised. Learning to read them takes about two minutes, and it is the single most useful thing a gold buyer can know.
What does 916 gold mean?
916 means 22 carat gold — 91.6% pure gold, with the remaining 8.4% made up of other metals such as copper, silver or zinc.
The number is simply the purity expressed in parts per thousand. Out of 1,000 parts, 916 are pure gold. Divide 22 by 24 (the carat scale) and you get 0.916 — which is where both the number and the name come from.
When a jeweller in Tamil Nadu says "916 thangam", they mean standard 22-carat jewellery gold. It is the purity used for almost all gold ornaments sold in India.
Carat, purity and fineness — the full table
| Carat | Fineness mark | Purity | Typically used for |
|---|---|---|---|
| 24K | 999 / 995 | 99.9% / 99.5% | Coins, bars, investment gold |
| 22K | 916 | 91.6% | Most Indian gold jewellery |
| 18K | 750 | 75.0% | Diamond and stone-set jewellery |
| 14K | 585 | 58.5% | Lightweight and western-style jewellery |
| 9K | 375 | 37.5% | Rare in India; common in export markets |
At today's rate, the difference is easy to see: 24K gold is per gram while 22K is per gram in Vellore (). The gap is the purity difference, not a discount.
Why is jewellery 22K and not pure 24K?
Pure gold is soft — soft enough to bend with your fingers and scratch against a fingernail. A 24K bangle would deform in daily wear and a 24K clasp would not survive a season.
Alloying gold with a small proportion of harder metals gives it the strength to hold a shape, take a polish, and survive being worn every day for decades. That is why 22K became the Indian jewellery standard, and why 18K is preferred for diamond settings, where prongs must grip stones securely.
The practical rule
Buy 24K when the purpose is investment — coins and bars. Buy 22K when the purpose is jewellery you will wear. Buy 18K when the piece is built around diamonds or coloured stones.
How to read a BIS hallmark
Since the current hallmarking regime came into force, a hallmarked gold ornament in India carries three marks. Older pieces may carry four or five, including a jeweller's mark and a year code, which have since been dropped.
- The BIS logo — a triangular mark of the Bureau of Indian Standards. This confirms the piece was tested at a BIS-recognised assaying and hallmarking centre.
- The purity/fineness grade — such as 22K916, 18K750 or 14K585. This is the tested purity, not the jeweller's claim.
- The six-digit HUID — a unique alphanumeric code, laser-engraved, that identifies your specific piece.
The marks are tiny and usually placed somewhere discreet: the clasp of a chain, the inner surface of a bangle, the post of an earring. A jeweller will show you where they are and can offer a loupe if you would like to see them clearly. Asking to see them is completely normal — do not feel awkward about it.
The HUID — and how to check it yourself
The HUID (Hallmark Unique Identification) is a six-character code assigned to each individual hallmarked article. No two pieces share one. It is the detail that makes modern hallmarking genuinely verifiable rather than merely decorative.
You can check it yourself:
- Download the BIS Care app, published by the Bureau of Indian Standards, from the Play Store or App Store.
- Open the "Verify HUID" option.
- Enter the six-digit code engraved on your ornament.
- The app returns the registered details of that piece — including the purity it was tested at and the hallmarking centre that tested it.
If the details on your screen do not match the piece in your hand, that is a genuine red flag worth raising with the jeweller immediately — and, if unresolved, with BIS through the same app.
Do this once, on your next purchase
Verify the HUID of one piece with the BIS Care app while you are still standing in the showroom. It takes under a minute, it tells you a great deal about the shop you are dealing with, and it costs nothing.
Is hallmarking compulsory in India?
Yes. Hallmarking of gold jewellery and artefacts is mandatory across the notified districts of India, which include all major jewellery markets. Registered jewellers may only sell hallmarked gold jewellery in the permitted purities, and each piece must carry a HUID.
The regime has been rolled out in phases since 2021 and the list of covered districts has expanded steadily. In practice, any established jeweller in Tamil Nadu today sells hallmarked gold as a matter of course.
A few sensible exemptions exist — for example, very lightweight items, certain export consignments, and some categories of traditional ornaments. If a jeweller tells you a particular piece is exempt, it is reasonable to ask why, and to get the answer in writing on the bill.
What about gold you already own?
Older family jewellery often predates the current system and may carry no hallmark, or only an old-style mark. This does not mean it is impure — a great deal of unhallmarked traditional gold is perfectly good 22K.
What it does mean is that its purity has not been independently certified, so when you exchange or sell it, the buyer will test it. Reputable jewellers do this openly, usually with an XRF machine that reads purity in seconds, and show you the reading before quoting.
If you are exchanging old gold:
- Ask to see the purity reading on the machine yourself.
- Ask what deduction, if any, applies for melting or refining loss.
- Get the assessed purity and weight written on your bill before the exchange is finalised.
At our showroom, hallmarking for certification of purity is one of the services we have offered for years, and we test and show old gold openly before any exchange.
Ask us anything about purity
Not sure what the marks on a piece mean? Send us a clear photograph on WhatsApp and we will tell you what it says.