How to Check Gold Purity: BIS Hallmark Guide 2026

By Vikas, BlueStone Editorial

To learn how to check gold purity, start with the BIS hallmark, match the karat mark to its fineness value, and verify the six character HUID in the BIS Care app. A visual check can screen a purchase, but only testing by a BIS recognized Assaying and Hallmarking Centre can provide an independent assay report when certainty matters.

TL;DR: Look for the BIS logo, a purity mark such as 22K916, and a unique HUID. Verify the HUID before buying, compare the invoice with the item, and use professional testing for old, unhallmarked, altered, or disputed jewellery. Treat magnet, scratch, colour, and bite tests as clues at most, never proof.

How to check gold purity: a six step process

A reliable purity check is a sequence, not a single trick. Start with the item itself, confirm the official identifiers, compare the paperwork, and escalate to a recognized laboratory when visual evidence is not enough.

Place the jewellery under bright, neutral light and find the tiny marks with a loupe rather than relying on colour.

Identify the BIS logo, the karat and fineness mark, and the six character alphanumeric HUID on a recently hallmarked item.

Match the mark to a recognized grade, such as 22K916, 18K750, or 14K585, instead of assuming that a deeper yellow colour means greater purity.

Keep these quick takeaways handy:

1. Open the official BIS Care app and use Verify HUID to compare the identifier with the item details shown.
2. Check that the invoice describes the article, net precious metal weight, purity in karat and fineness, and hallmarking information.
3. Inspect every item in a pair and every detachable part because BIS says each should carry its own hallmark and HUID.
4. Pause the purchase if a mark is blurred, incomplete, inconsistent with the invoice, or not verifiable.
5. Ask the seller to show the hallmark with the magnifying glass kept at the outlet and to display its BIS registration.
6. Choose professional testing at a BIS recognized centre when the item is old, unhallmarked, altered, inherited, or involved in a purity dispute.

Gold purity marks explained: karat and fineness

Karat and fineness describe the declared proportion of gold in an alloy. The current BIS hallmarking FAQ lists six permitted gold grades under IS 1417:2016. The percentage column below is a direct conversion from fineness parts per thousand.

Hallmark grade	Fineness	Gold content expressed as a percentage
14K585	585	58.5%
18K750	750	75.0%
20K833	833	83.3%
22K916	916	91.6%
23K958	958	95.8%
24KS995	995	99.5%

Karat describes gold as parts out of twenty four, while fineness states pure gold parts per thousand.

The mark 22K916 means the declared fineness is 916 parts of gold per thousand, commonly expressed as 91.6 percent.

The mark 18K750 means 750 parts of gold per thousand, commonly expressed as 75 percent.

Keep these quick takeaways handy:

1. The mark 14K585 means 585 parts of gold per thousand, commonly expressed as 58.5 percent.
2. BIS also lists 20K833, 23K958, and 24KS995 among grades permitted for hallmarking under the cited standard.
3. Higher karat does not automatically mean a design is more suitable for daily wear because alloy choice also affects hardness and colour.
4. White gold and rose gold can be genuine gold alloys even though their colour differs from yellow gold.
5. A karat stamp by itself is less useful than the complete BIS hallmark and a verifiable HUID for a recent Indian retail purchase.
6. Read the purity mark as a declared grade, then verify its identity and seek an assay if you need independent confirmation.

How to read a BIS hallmark and HUID

According to the BIS hallmarking FAQ, a gold hallmark introduced with HUID contains the BIS logo, purity in karat and fineness, and a six character alphanumeric HUID. Read all three together.

A current BIS hallmark on gold jewellery has three core parts: the BIS logo, purity in karat and fineness, and a unique HUID.

The HUID is a six character alphanumeric identifier that makes a hallmarked article traceable in the BIS system.

The purity component should combine karat and fineness, for example 18K750, rather than leaving the buyer to infer the grade.

Keep these quick takeaways handy:

1. Use a loupe because the mark may be very small on a ring, earring post, clasp, pendant back, or bangle interior.
2. Do not confuse a brand mark, maker mark, or design code with the BIS logo or HUID.
3. For earrings and other pairs, inspect both pieces and verify their individual identifiers.
4. For detachable parts, check each removable component instead of assuming one hallmark covers the full article.
5. If polishing, resizing, repair, or wear has made a mark difficult to read, do not guess from a partial sequence.
6. Ask for the seller's BIS registration details and keep the invoice with the jewellery for future redressal.

Gold jewellery examples for a purity check

Different jewellery forms place tiny purity marks in different locations. Use these real BlueStone examples to practise the inspection sequence: look near a clasp on chains and bracelets, inside a ring or bangle, behind a pendant, and on each earring. Product images help with orientation, but the engraved hallmark, HUID verification, invoice, and professional assay remain the evidence that matters.

How to verify HUID in the BIS Care app

The official BIS Care app page lists Verify HUID as the feature for authenticating a hallmarked jewellery item. Verification is strongest when the engraving on the item, the app result, and the invoice all agree.

Download the official BIS Care app from the link provided on the Bureau of Indian Standards website.

Choose the Verify HUID feature and enter the six character code exactly as it appears on the jewellery.

Compare the returned details with the article, purity mark, and seller information in front of you.

Keep these quick takeaways handy:

1. Recheck letters and numbers if the first lookup fails because tiny engravings can be easy to misread.
2. Ask the jeweller to help locate the full identifier under magnification without accepting a code from a tag alone.
3. Treat a mismatch between the app result, jewellery mark, and invoice as a reason to stop and clarify before paying.
4. Verify each HUID separately when buying a pair or an item with detachable hallmarked components.
5. Save the invoice and product details after purchase, but do not publish the HUID in social posts or resale listings.
6. Use the app as an identity check and professional assay testing as the stronger option when actual purity is disputed.

Can you check gold purity at home?

You can perform safe screening at home, but you cannot establish fineness by colour, feel, or one simple household test. Use home checks to decide whether professional confirmation is needed, not to issue your own purity verdict.

At home, you can inspect marks, verify HUID, compare documents, and notice obvious inconsistencies without damaging the jewellery.

A magnet can reveal some strongly magnetic base metal, but a nonmagnetic result does not prove that an item has the declared gold purity.

Colour is unreliable because alloys, plating, lighting, surface wear, and polishing can change how gold appears.

Keep these quick takeaways handy:

1. Avoid biting gold because it is unsafe, can damage the jewellery, and cannot identify fineness reliably.
2. Avoid rubbing jewellery on ceramic because scratches and streaks are ambiguous and may harm the finish.
3. Do not use household acid or chemical kits without training because they can injure skin, damage surfaces, and test only a small area.
4. Electronic testers can be useful screening tools, but calibration, surface condition, and plating can affect a reading.
5. A density calculation is difficult for stone set or hollow jewellery because gemstones, voids, solder, and mixed parts distort the result.
6. For a valuable purchase or dispute, move from home screening to a documented professional assay.

When to use professional gold purity testing

The BIS hallmarking overview says consumers can get jewellery tested at a BIS recognized Assaying and Hallmarking Centre and receive an assay report. This is the appropriate next step for uncertainty or a dispute.

Use professional testing when jewellery has no hallmark, an unreadable mark, a failed HUID check, or details that conflict with the invoice.

Inherited and old jewellery often needs testing because age, repairs, solder, and replaced parts can make visual assessment uncertain.

Altered, resized, or heavily repaired jewellery deserves a fresh check when the purity of added material matters.

Keep these quick takeaways handy:

1. A BIS recognized Assaying and Hallmarking Centre can test consumer jewellery and issue an assay report with article identification.
2. Ask whether the method is nondestructive or requires sampling before you consent, especially for sentimental pieces.
3. Keep photographs, the invoice, HUID details, and the assay report together if you are raising a purity concern.
4. If hallmarked jewellery tests below its marked purity, use the BIS consumer protection route and the seller's documented details.
5. Do not accept an undocumented verbal estimate as equivalent to a recognized assay report.
6. For resale or exchange, ask the receiving jeweller which test method and deductions apply before handing over the piece.

Common mistakes when checking gold purity

Most errors come from treating one clue as proof. A complete check connects the physical mark, official HUID record, invoice, and, when necessary, an independent assay.

Judging purity from yellow colour alone ignores the effect of alloy composition, plating, lighting, and surface finish.

Reading only 916 or 750 without checking the BIS logo and HUID leaves the identity check incomplete.

Verifying a code from a tag instead of the engraving on the jewellery can connect the lookup to the wrong item.

Keep these quick takeaways handy:

1. Checking only one earring or one detachable part overlooks the requirement for separate identifiers.
2. Assuming all gold marked twenty two karat is equally suitable for every design confuses purity with durability and construction.
3. Using a destructive home test can damage a surface while still producing an uncertain result.
4. Leaving without a detailed invoice removes an important record for comparison and complaint handling.
5. Treating a failed app lookup as proof of fraud is premature until you recheck every character and ask for clarification.
6. Ignoring an inconsistency because the design looks attractive puts appearance ahead of a basic buyer protection check.

Gold purity checklist before you buy

The BIS jeweller FAQ explains the details that should appear on an invoice for hallmarked precious metal articles. Use the checklist below while the item and seller records are available together.

Confirm that the seller displays a valid BIS registration and offers hallmarked jewellery where required.

Use magnification to find the BIS logo, karat and fineness mark, and six character HUID on the item itself.

Verify the HUID in the official BIS Care app before completing the purchase.

Keep these quick takeaways handy:

1. Match the returned information to the item, purity mark, seller details, and invoice.
2. Inspect both items in a pair and each detachable part for its own hallmark and identifier.
3. Ask the invoice to state the article description, net precious metal weight, purity in karat and fineness, and hallmarking information.
4. Clarify whether stones, enamel, beads, and other non gold materials are excluded from net precious metal weight.
5. Keep the invoice and HUID record in a secure place after purchase.
6. Choose a BIS recognized Assaying and Hallmarking Centre if any detail remains disputed or if independent confirmation matters.

Official sources used for this gold purity guide

This guide relies on current Bureau of Indian Standards pages for hallmark components, HUID verification, seller duties, consumer testing, and redressal. The BIS consumer protection page is the main reference for testing and purity complaints.

The Bureau of Indian Standards hallmarking overview defines hallmarking and explains consumer testing through recognized centres.

The BIS hallmarking FAQ lists permitted gold grades and the three components of a current gold hallmark.

The BIS Care page describes the Verify HUID feature for hallmarked jewellery.

Keep these quick takeaways handy:

1. The BIS consumer protection page explains recognized centre testing, HUID verification, and redressal when marked purity is deficient.
2. The BIS jeweller FAQ lists invoice details and seller responsibilities for hallmarked precious metal articles.
3. Official information can change, so buyers should check the linked BIS pages at the time of purchase.
4. This guide does not replace an assay report or advice from the relevant authority in a specific dispute.
5. No competitor page was supplied or used to build the article structure.
6. Natural phrases beyond the primary keyword were inferred from buyer intent and current BIS guidance.

How to use this guide before buying

Save the six step process, open the official BIS Care app before you visit the store, and compare the jewellery, HUID result, and invoice while they are together. If any detail remains uncertain, pause the purchase and ask for testing by a BIS recognized Assaying and Hallmarking Centre.

More gold jewellery buying guides

Continue with BlueStone guides to choosing a gold chain, choosing a gold ring, understanding gold bangle styles, and buying gold coins.

Frequently Asked Questions about How to Check Gold Purity

What is the easiest way to check gold purity before buying?

The easiest reliable screen is to inspect the BIS logo, karat and fineness mark, and six character HUID, then verify that HUID in the official BIS Care app. Compare the result with the jewellery and invoice. If anything conflicts, pause the purchase and ask for clarification or professional testing.

What does 916 mean on gold jewellery?

The mark 916 states a fineness of 916 parts of gold per thousand, commonly expressed as 91.6 percent and associated with 22K gold. On a recent hallmarked item, read it as part of the complete mark, such as 22K916, and also check the BIS logo and HUID.

How do I verify a gold jewellery HUID?

Use the Verify HUID feature in the official BIS Care app. Enter the six character alphanumeric code engraved on the jewellery, then compare the returned information with the item, purity mark, seller, and invoice. Recheck easily confused letters and numbers before treating a failed lookup as a mismatch.

Does a magnet test prove that gold is pure?

No. A strong magnetic response may reveal some base metal, but a nonmagnetic result does not prove the declared fineness. Many non gold metals are also nonmagnetic, while clasps and components can behave differently. Use the magnet only as a rough clue, then rely on hallmark checks and professional testing.

Can old or inherited gold jewellery be tested?

Yes. BIS says consumers can approach a recognized Assaying and Hallmarking Centre for testing of jewellery and receive an assay report. Ask about the proposed method and whether sampling is required before testing a sentimental item. Repairs, solder, and replacement parts can make old jewellery harder to assess visually.

Should both earrings have a hallmark and HUID?

Yes. BIS guidance says each article in a pair and each detachable part should carry a hallmark with a different HUID. Check both earrings rather than assuming one identifier covers the pair. Use magnification, verify each code separately, and compare the purchase details with the invoice.

What should a gold jewellery invoice include?

BIS guidance says the invoice for a hallmarked precious metal article should identify the article and state the net precious metal weight, purity in karat and fineness, and hallmarking information. Keep the invoice with the HUID record because it supports comparison, resale discussions, and complaint redressal if a purity issue arises.

Conclusion

The safest way to check gold purity is to combine three actions: inspect the complete BIS hallmark, verify the HUID in the official BIS Care app, and keep a detailed invoice. Home checks can help you notice a problem, but they cannot replace a recognized assay when the mark is missing, the item is old, or the purity is disputed. Before your next purchase, take one minute to verify the item instead of relying on colour or trust alone.