Buying gold or diamond jewellery involves more than checking the price and the purity of the metal. A BIS hallmark confirms the purity of the gold, but it does not certify the quality or authenticity of every diamond, gemstone or other component set in a piece.
Understanding this distinction can help consumers make informed choices when purchasing jewellery, particularly during the festive season and Dhanteras.
The difference is especially relevant for diamond jewellery and traditional designs such as Polki and Jadau, where the value of a piece can depend on the stones, the gold and the craftsmanship.
What does a BIS hallmark actually certify?
Hallmarking is the official determination and recording of the proportion of precious metal in a jewellery article. In India, the Bureau of Indian Standards (BIS) operates the hallmarking system for gold and silver.
A hallmarked gold jewellery article carries three markings: the BIS logo, the purity of gold expressed in carats and fineness, and a six-digit alphanumeric Hallmark Unique Identification (HUID) number.
For instance, a 22-carat gold article carries a fineness marking of 916, indicating 916 parts of gold per 1,000 parts of the alloy. An 18-carat article carries a fineness marking of 750.
Consumers can use the ‘Verify HUID’ facility on the BIS Care app to check the details associated with a hallmarked gold article.
However, the hallmark is not a certification of every material used in the jewellery. It establishes the purity of the gold, not the quality or authenticity of the stones set in it.
Does a hallmark guarantee diamond quality?
No. A gold hallmark and a diamond grading report serve different purposes.
A hallmark indicates the purity of the gold, while a diamond grading report provides information about a diamond’s characteristics. These may include cut, colour, clarity and carat weight, commonly known as the four Cs.
Jia Dholakia, Head of Design at Verlas, a direct-to-consumer fine jewellery brand, said consumers should understand this distinction when buying diamond jewellery because the gold and the diamond contribute differently to the piece.
“BIS hallmarking is an important safeguard when purchasing gold jewellery, but it does not verify the quality of diamonds or other components,” Dholakia said.
She said buyers should understand what the hallmark verifies and what the diamond certification covers. Independent grading organisations such as the International Gemological Institute (IGI) and the Gemological Institute of America (GIA) provide diamond grading reports.
A grading report should be considered separately from the gold hallmark. Buyers should check the report’s details and establish whether they correspond to the diamond being offered for sale.
What should buyers check in Polki and Jadau jewellery?
The distinction also matters when purchasing traditional jewellery such as Polki and Jadau, which can feature uncut diamonds, coloured gemstones, gold and intricate craftsmanship.
Dilip Dassani, Partner at Dassani Brothers, an Indian luxury jewellery manufacturer and brand, said a hallmark confirms the purity of gold but does not establish the authenticity, quality or origin of every stone set in a piece.
“A hallmark serves a very specific purpose: it confirms the purity of the gold, not the authenticity, quality or origin of every stone set in a piece of jewellery,” Dassani said.
He said buyers should ask about stone quality, treatments and disclosures, particularly in traditional jewellery, where the stones and workmanship can contribute to the value alongside the gold.
For consumers, the takeaway is to seek clear information about the different elements of the piece instead of treating the gold hallmark as a guarantee of the entire jewellery article.
What should consumers check before buying jewellery?
Before making a purchase, buyers should check the following:
- Gold purity: Look for the BIS hallmark and check the caratage or fineness marking. Verify the HUID using the BIS Care app.
- Diamond grading: For diamond jewellery, ask for the relevant grading report, where available, and check the characteristics it records.
- Gemstones and treatments: For Polki, Jadau and coloured-stone jewellery, ask the jeweller about the stones used, their quality, any treatments and the disclosures available.
- Weight and billing: Check the net weight of the precious metal and the details mentioned on the invoice. Ask the jeweller to clarify how the gold, stones and workmanship contribute to the final price.
- Documentation: Retain the invoice and any diamond grading reports or other documentation provided with the purchase.
BIS also allows consumers to get hallmarked jewellery tested for precious-metal purity at a BIS-recognised Assaying and Hallmarking Centre, subject to applicable testing charges.