BIS Hallmark 916, 750 and 585 — Gold Purity Fully Explained

When you look at a gold ornament and see the numbers 916, 750, or 585 stamped on it alongside the BIS logo, what do these numbers mean? How do you know if the hallmark is genuine? And what happens if a piece has no hallmark at all? This article explains India's gold hallmarking system in complete detail — from the origin of BIS standards to the revolutionary HUID system that makes fraud vastly more difficult in 2026.

What is BIS Hallmarking?

BIS hallmarking is a quality certification system administered by the Bureau of Indian Standards (BIS), a statutory body operating under the BIS Act 2016 and the Ministry of Consumer Affairs, Food and Public Distribution. A hallmark is a guarantee that the metal in a piece of jewellery meets the purity standard it claims to meet.

Gold jewellers registered with BIS send their pieces to BIS-recognised Assaying and Hallmarking Centres (AHCs) — independent laboratories equipped with X-ray fluorescence (XRF) spectrometers and fire assay facilities that measure gold purity to three decimal places. Once a piece passes testing, it receives the hallmark — and under the HUID system since 2022, a unique laser-etched identification code.

Under the mandatory hallmarking order effective from June 2021 (extended in phases), all jewellers with BIS licences must sell only BIS-hallmarked gold jewellery. As of April 2023, this is enforced across all districts in India, with penalties up to ₹1 lakh or five times the price of the article for violations under the BIS Act.

The HUID System: India's Anti-Fraud Innovation

Prior to 2022, hallmarks consisted only of the BIS logo, purity mark, and assaying centre code. These could be forged using stamps. The HUID (Hallmark Unique Identification) system, introduced in April 2022 and made mandatory from April 2023, adds a 6-character alphanumeric code laser-etched on each piece that links it to a centralised BIS database.

The HUID database entry is created at the time of assaying and records: the jeweller's name and BIS licence, the assaying centre, the purity grade, and the registration date. A fake HUID will either not appear in the database or will show different jeweller details than the shop selling the piece.

Gold Purity Reference Table

Why 916 Dominates Indian Jewellery

22K gold (916 purity) has been the preferred standard in India for centuries. The reasons are practical and cultural. 22K gold has sufficient purity to retain the characteristic deep yellow colour Indians associate with gold — 18K gold (which contains 25% alloy) can appear more "pale" or "cool," especially in rose gold and white gold alloys. 22K is also soft enough to be worked into fine filigree and traditional designs by karigars (goldsmiths) who have refined their techniques for this specific gold hardness over generations.

The 8.4% alloy in 22K is typically copper (which deepens yellow colour) and silver or zinc (which provides hardness). The exact alloy composition is not specified in the BIS standard — only the gold content minimum of 91.6% is mandated.

How to Read a Complete BIS Hallmark Stamp

Under the current mandatory hallmarking system (HUID era), a complete hallmark stamp on a piece of gold jewellery contains:

What Happens if a Hallmark is Fake or Missing?

Selling gold jewellery without a BIS hallmark (or with a fake hallmark) by a licensed jeweller is an offence under the BIS Act 2016. Penalties include:

• Fine up to ₹1 lakh or five times the article's value, whichever is higher
• Imprisonment up to one year for repeat offences
• Cancellation of BIS licence
• Seizure of unmarked stock

As a consumer, if you suspect a hallmark is fake (HUID does not verify, purity different from claimed), you can report using the BIS Care app under the "Complaint" section, or email hallmark@bis.gov.in. BIS enforcement teams conduct regular market surveillance.

Frequently Asked Questions

Is all gold sold in India now hallmarked?

Mandatory hallmarking applies to all BIS-licensed jewellers in notified districts. As of 2024, coverage extends to all districts of India. Unlicensed sellers and some remote market vendors may still sell un-hallmarked gold, but this is illegal for licensed businesses.

What does BIS 916 mean on gold jewellery?

BIS 916 means the piece has been tested and certified to contain at least 91.6% pure gold — corresponding to 22 karat gold. The remaining 8.4% is alloy metal (copper, silver, zinc) added for hardness and durability. This is the most commonly traded purity for jewellery in India.

Can I hallmark my own jewellery at home?

No. Hallmarking requires laboratory assay testing at a BIS-recognised Assaying and Hallmarking Centre. Home testing (acid test kits) can give approximate purity readings but are not BIS-standard. The HUID laser etching can only be done by accredited centres. You can find the nearest AHC on the bis.gov.in website.

Does platinum or silver have a similar hallmarking system?

BIS hallmarking for silver jewellery is voluntary (not mandatory as of 2026), though many reputable jewellers do provide it. Hallmarked silver uses purity marks like 925 (Sterling) and 999 (fine silver). Platinum hallmarking is also voluntary and uses marks like 950 or 900.

What if my old gold jewellery has no hallmark?

Older gold pieces purchased before mandatory hallmarking are still legitimate. You can have them hallmarked retroactively at a BIS-accredited AHC for a small fee (typically ₹35–₹45 per piece). This is useful if you plan to sell the piece, as a hallmark significantly increases buyer confidence and resale value.