Most Indians today are holding a piece of gold that was inherited, gifted, or bought years ago without a bill of sale. Now, before you sell it, pledge it for a loan, or decide whether it’s worth keeping, you need to know if it’s actually what it claims to be.
Learning how to check gold purity at home will not give you a lab certificate. But it will quickly tell you whether a piece deserves further trust or scrutiny, without damaging it.
Know the five common methods, ranked from most to least reliable.
What Gold Purity Markings Actually Mean
Before testing anything, understand what you’re looking for.
In India, gold purity is usually expressed in two ways:
- Karats (K): 24K = 99.9% pure, 22K = 91.6% pure, 18K = 75% pure
- Fineness numbers: 999 (24K), 916 (22K), 750 (18K), 585 (14K)
These may appear as stamps, such as 22K916 or 18K750, on hallmarked pieces. Since June 2021, hallmarking has been mandatory for registered jewellers in notified districts to sell gold jewellery and artefacts, subject to BIS rules and exemptions.
5 Methods to Check Gold Purity at Home, Ranked by Reliability
1. BIS Hallmark + HUID Verification — Most Reliable
What to do:
- Use a magnifying glass to look for the hallmark on an inconspicuous area, such as the inner band of a ring, the clasp of a chain, or the back of a pendant.
- Look for three marks: BIS logo (triangle), purity in K and fineness (e.g. 22K916), and a 6-digit alphanumeric HUID code
- Download the BIS CARE app (Android/iOS), tap “Verify HUID,” and enter the code
- The app may show details such as the purity grade, jeweller name, assaying centre, and hallmarking date.
Why it’s the most reliable: The HUID is unique to each piece and recorded in the BIS database. A forged stamp can’t fake a database entry. This is the closest thing to a home-level lab result.
Limitation: This works only for jewellery that carries a valid HUID. Older hallmarked pieces or inherited jewellery may not have one.
2. Ceramic Scratch Test — Useful Screening Test
What to do:
- Get an unglazed ceramic tile or the unglazed underside of a ceramic plate
- Drag the gold item gently across the surface
- Genuine gold may leave a golden-yellow streak, while many base metals leave a black or grey mark.
Why it works: Gold’s chemical inertness means it doesn’t oxidise when scratched. Many base metals do.
Limitation: Test only on a hidden surface, because the scratch may be visible. Gold-plated items with a thick coating may pass if only the surface gold contacts the tile. Pair it with another test.
3. Magnet Test — Good for Ruling Out Fakes
What to do:
- Use a strong neodymium magnet (fridge magnets won’t work)
- Hold it close to the gold piece
- Attraction → ferrous metals present → not pure gold
- No attraction → not conclusive, but it passes this basic screen
Why it works: Pure gold is not attracted to a magnet, so any strong attraction suggests the presence of ferrous or magnetic metals.
Limitation: Many counterfeit gold items are made of non-magnetic metals such as copper or zinc. Passing this test doesn’t confirm purity. It only eliminates a specific type of fake. Use it first as a quick filter, not a final answer.
4. Float Test — Very Basic, Limited Precision
What to do:
- Fill a glass with water
- Drop the gold item in gently
- Real gold (density ~19.3 g/cm³) sinks immediately and stays at the bottom
- If the item floats, it is almost certainly not solid gold. If it sinks, that does not prove purity because many base metals and plated items will also sink.
Why it works: Gold is one of the densest metals. Most fakes use lighter alloys that don’t match that density.
Limitation: A thick, gold-plated item with a heavy base-metal core (such as brass) will also sink. This test catches obvious fakes like hollow items and thin-coated alloys, but won’t differentiate 18K from 22K. It is useful as a first pass, not as a standalone verdict.
5. Vinegar Test — Indicative, Not Definitive
What to do:
- Apply a few drops of white vinegar to the surface, or soak the item for 2–3 minutes
- No colour change is a positive sign, but it does not prove purity, especially if the item is gold-plated.
- Darkening, greenish tint, or surface corrosion = base metals present
- Avoid using vinegar on jewellery with stones, enamel, pearls, or delicate finishes.
Why it works: Gold is chemically inert to acetic acid. Most base metals react and corrode.
Limitation: Thick gold plating can mask the base metal beneath for short exposure. Don’t rely on this alone for valuable pieces, and test on a discreet area.
For a fuller comparison of what 24K means versus 22K and 18K for investment purposes, read 24K vs 22K vs 18K: How to Differentiate?
What Each Test Can and Cannot Tell You
| Method | Detects fake gold | Confirms exact karat | Safe for jewellery | Works on old pieces |
| BIS HUID App | ✓ | ✓ | ✓ | Only post-2021 pieces |
| Ceramic scratch | ✓ | Partial | Minor surface mark | ✓ |
| Magnet | Partial | ✗ | ✓ | ✓ |
| Float test | Partial | ✗ | ✓ | ✓ |
| Vinegar | Partial | ✗ | Test a discreet area | ✓ |
Run at least two methods together. A piece that passes the HUID check, leaves a gold streak on ceramic, and doesn’t react to vinegar has given you three independent signals. That’s meaningful confidence.
When Home Tests Aren’t Enough: Get XRF Testing
For pieces valued above ₹50,000, inherited jewellery without bills, or any item you plan to pledge for a gold loan or sell, home tests should be treated as a starting point, not a final answer.
XRF (X-ray fluorescence) testing is:
- Non-destructive: no scratching, melting, or chemicals
- Precise: gives you exact purity percentage, not just “real or fake”
- Widely available: most jewellers, including Tanishq, offer free Karatmeter checks
- Available at BIS-accredited Assaying and Hallmarking Centres (find one at bis.gov.in)
If home tests give you conflicting results or the piece is high-value, XRF is the most practical non-destructive test for settling the question.
The Purity Question You Never Have to Ask About Digital Gold
Every method above exists because physical gold carries purity uncertainty at the point of purchase and beyond. That’s the nature of the format.
When you invest in digital gold through SafeGold, the purity question is addressed before you spend a rupee. Every gram on the platform is 24K, 99.99% purity, independently verified and audited by a third-party trustee, stored in Brinks vaults, and insured.
When you want physical gold (coins, bars), SafeGold delivers certified, BIS-compliant pieces to your door. The purity chain runs from the vault to your hands without a gap.
If you’re holding physical gold you’ve already verified and want it to earn rather than sit idle, SafeGold Gains lets you lease it at 4% p.a., paid monthly in grams of gold.
Conclusion
Home testing gives you a reliable first filter. The BIS HUID app is your strongest tool for any post-2021 hallmarked piece. For older jewellery or high-value items, follow it with a professional XRF check before making any financial decision.
For all new gold investments, the smarter move is to start with a format in which purity is verified upfront rather than checked after the fact. Build your 24K gold position on SafeGold from ₹10, and keep the magnifying glass for the pieces you already own.
FAQs
Q. What is the most reliable way to check gold purity at home?
A. The BIS HUID check via the BIS CARE app is the most reliable home method for post-2021 hallmarked jewellery. It cross-references the piece against a government database. For older pieces without a HUID, combine multiple screening methods and get an XRF check before selling, pledging, or making a high-value decision.
Q. What does 916 mean on gold jewellery?
A. 916 is the fineness mark for 22K gold. The piece contains 91.6% pure gold. It’s the most common standard for Indian jewellery. 999 indicates 24K gold of 99.9% purity and is used for investment-grade coins, bars, and digital gold.
Q. Can the magnet test confirm gold purity?
A. No. The magnet test only helps rule out items that contain ferrous or strongly magnetic metals. Many counterfeit alloys use non-magnetic metals like copper or zinc, which pass the magnet test. Use it as a first filter, not a standalone verdict.
Q. Where can I get gold professionally tested in India?
A. Visit a BIS-accredited Assaying and Hallmarking Centre. Find the nearest one at bis.gov.in. Many jewellers offer Karatmeter or XRF checks. Tanishq, for example, offers free Karatmeter testing in every store, including for jewellery bought elsewhere.
Q. Is digital gold purer than hallmarked jewellery?
A. Yes. SafeGold’s digital gold is 24K, 999.9 fineness, the highest investment-grade standard. Most hallmarked jewellery is 22K (91.6% pure) or 18K (75% pure), alloyed for durability. At resale, you’re paid only for the pure gold content, which makes the purity grade directly relevant to investment value.