Glossary

Pure gold (24K) is too soft for everyday jewellery, so it is alloyed with metals like copper, silver, or zinc to increase hardness and allow different colours — yellow gold uses copper and silver, white gold uses palladium or nickel, and rose gold uses a higher proportion of copper. The karat rating of a gold article directly reflects how much pure gold versus alloying metal it contains.

In a hallmarking context, assaying is the scientific testing of gold, silver, or other precious metals using methods like XRF spectrometry or fire assay (cupellation) to determine the exact percentage of pure metal present.

BIS operates under the Ministry of Consumer Affairs, Food & Public Distribution and sets quality standards for gold and silver articles. All hallmarking in India must be done through BIS-authorized centres.

The BIS hallmark consists of a triangular BIS logo, purity/fineness number (e.g. 916 for 22K gold), and a unique six-digit HUID number. It provides consumers with an assurance of purity from an independent testing laboratory.

Most organised Indian jewellers offer a buyback or lifetime exchange policy where hallmarked gold jewellery can be sold back at 90–100% of the current gold value based on net weight, subject to a purity test. The original tax invoice is typically required, and a deduction for making charges or wastage usually applies.

Caratage divides gold content into 24 equal parts — 22-carat gold contains 22 parts gold and 2 parts other metals (91.67% pure). In India, BIS hallmarking certifies gold at standard caratages of 14K (585 fineness), 18K (750), 20K (833), 22K (916), 23K (958), and 24K (999). The caratage is stamped on every hallmarked article alongside the fineness number.

Lost-wax casting is the most common technique in India's jewellery industry: a wax model of the ornament is encased in plaster, the wax is melted out, and molten gold or silver is poured into the resulting cavity. Casting enables mass production of intricate designs that would be difficult to achieve by hand fabrication, and the finished piece still requires hallmarking before sale.

Available through apps such as Paytm, PhonePe, and Google Pay, digital gold purchases attract 3% GST and can later be converted into physical coins, bars, or jewellery via partner jewellers. Digital gold is currently not regulated by SEBI or RBI, which has prompted investor advisories about counterparty risk.

In electroplating, the article is immersed in a solution containing dissolved gold or silver ions and an electric current causes the precious metal to bond to the surface. Electroplated jewellery — sometimes marked GP (gold plated) or GE (gold electroplate) — is significantly cheaper than solid gold but cannot be hallmarked under BIS standards, as hallmarking certifies the purity of the entire article, not just a surface coating.

Meenakari is a centuries-old Indian enamelling art, particularly associated with Jaipur and Lucknow. Artisans fill engraved grooves in gold or silver with powdered glass and fire the piece in a kiln to fuse the enamel. Because enamel adds non-metal weight, consumers should ensure their invoice distinguishes net gold weight from gross weight when buying meenakari jewellery.

Fineness is the standard system used in hallmarking to denote purity. For gold: 999 = 24K (pure gold), 916 = 22K, 750 = 18K, 585 = 14K. For silver: 999 = pure silver, 925 = sterling silver. The fineness number is stamped directly on the hallmarked article.

Fire assay involves taking a small sample of the metal, wrapping it with lead foil, and heating it in a cupel (a porous ceramic crucible) at temperatures above 1,000°C. The base metals are absorbed into the cupel, leaving behind a bead of pure precious metal that is then weighed. It is considered the referee method for precious metal analysis.

Gold ETFs are listed on Indian stock exchanges and regulated by SEBI, allowing investors to buy and sell gold exposure during market hours through a demat account. The fund house holds equivalent physical gold in secured vaults, so investors benefit from gold price movements without storage or purity concerns.

Gold loans are one of the most popular forms of secured lending in India, offered by banks and NBFCs. The lender assesses purity (typically 18K–24K) using XRF or karat meters, calculates the net gold weight, and disburses funds accordingly — as per RBI guidelines, up to 75% of the gold's market value. The pledged gold is stored in secure vaults and returned upon full repayment.

A Good Delivery gold bar weighs approximately 400 troy ounces (about 12.4 kg) and must be at least 99.5% pure, produced by an LBMA-accredited refiner, and stamped with the refiner's mark, purity, year, and serial number. In India, MCX-traded gold contracts also reference LBMA Good Delivery standards, making it the benchmark that connects India's bullion market to the international trading system.

When purchasing jewellery in India, the bill should clearly state both the gross weight and the net weight (weight of the precious metal alone). Consumers should pay the gold rate only on the net gold weight, not on the weight of diamonds, stones, or enamel work. Understanding this distinction protects buyers from overpaying.

When purchasing gold jewellery in India, buyers pay 3% GST on the gold value and 5% GST on the making charges. Exchanging old gold jewellery for new is treated as a sale-and-purchase transaction. Gold jewellery exporters registered with a notified agency may also receive GST exemptions on gold supply.

Introduced by BIS in July 2021, the HUID system replaced the older jeweller's mark. Each piece of hallmarked jewellery receives a unique six-character alphanumeric code that can be verified online via the BIS Care app, enabling end-to-end traceability from assaying centre to consumer.

Founded in 1919 and headquartered in Mumbai, IBJA publishes AM and PM opening/closing rates for gold (999, 995, 916, 750, 585) and silver (999) that serve as official benchmarks. These rates are used by the RBI for Sovereign Gold Bond pricing, by banks for gold loan valuations, and by jewellers nationwide for retail pricing.

Common impurities in gold jewellery include copper, silver, zinc, and nickel — metals deliberately added to create durable alloys, or inadvertently introduced during manufacturing. Assaying methods such as XRF and fire assay are used by hallmarking centres to detect and quantify these impurities, ensuring the article meets its declared karat or fineness grade.

Ingots are produced by pouring molten metal into a mould and allowing it to cool into a solid bar. Gold and silver ingots typically carry markings indicating the refiner's name, weight, and purity (e.g. 999.9 fineness). In India, ingots arriving from LBMA-approved refineries serve as the raw material that is eventually alloyed, fashioned into jewellery, and sent for BIS hallmarking.

Before the HUID system was introduced in 2021, the jeweller's identification mark was one of the four mandatory components of the BIS hallmark. It allowed consumers and authorities to trace a piece of jewellery back to the specific jeweller who manufactured or sold it. While HUID has now largely taken over the traceability function, jewellers must still hold a valid BIS registration to sell hallmarked gold and silver articles.

Job work is a cornerstone of India's jewellery supply chain. The jeweller retains ownership of the precious metal while the karigar charges a making fee based on weight or piece count. Under GST, job work on gold and precious metals attracts a concessional rate, and the metal must be returned or converted within the prescribed time limit. Hallmarking obligations apply to the finished article before it is sold to consumers.

The karat system divides gold purity into 24 parts. 22K gold means 22 parts gold and 2 parts other metals (91.6% pure gold). Common standards in India include 24K (999), 22K (916), 18K (750), and 14K (585).

Kilo bars are among the most commonly traded bar sizes in the global and Indian bullion markets. Gold kilo bars are typically refined to 995 or 999.9 fineness and carry the refiner's stamp, serial number, and weight. In India, jewellery manufacturers frequently handle kilo bars as feedstock that is melted, alloyed to the desired karat, and fabricated into ornaments.

Originating in Rajasthan and flourishing under Mughal patronage, Kundan work involves embedding uncut gemstones or glass into a lac (resin) core and securing them with thin strips of pure 24K gold foil. It remains a hallmark of bridal jewellery in India and is often combined with Meenakari enamel work on the reverse side of pieces.

Originating in 1919, the London Gold Fix (now officially the LBMA Gold Price) is determined via an electronic auction managed by ICE Benchmark Administration. The gold price is fixed at 10:30 AM and 3:00 PM London time each business day. Indian bullion dealers and jewellers reference the London Fix — along with the domestic MCX price and the INR/USD exchange rate — to arrive at local gold and silver prices.

Making charges cover labour, craftsmanship, design complexity, and overheads involved in converting raw gold or silver into finished jewellery. In India they are typically quoted either as a fixed rate per gram or as a percentage of the gold value. Intricate designs like bridal sets carry higher making charges than plain bands or chains.

MCX offers standardised gold futures in multiple lot sizes (Gold, Gold Mini, Gold Guinea, Gold Petal) allowing traders to take leveraged positions by depositing a margin rather than the full contract value. MCX gold prices serve as a key benchmark for the domestic bullion market and are widely tracked by jewellers and bullion dealers.

Millesimal fineness is the standard used in BIS hallmarking. Common stamps include 999 (24K, near-pure), 916 (22K), 750 (18K), and 585 (14K) for gold, and 999 or 925 (sterling) for silver. The three-digit fineness number is engraved directly on every hallmarked article in India.

NABL is a constituent board of the Quality Council of India under the Ministry of Commerce and Industry. It certifies the technical competence of testing and calibration laboratories following ISO/IEC 17025 standards. Gold refineries seeking a BIS license to produce standard gold bars must hold NABL accreditation, ensuring their assay results are internationally recognised.

Net weight is calculated by subtracting the weight of stones, meena (enamel), and any non-gold or non-silver elements from the gross (total) weight of the article. In India, the price of gold jewellery and the valuation for gold loans are both based on net weight multiplied by the prevailing per-gram rate and the purity factor.

In numismatics and bullion trading, the obverse is the principal face of a coin. On Indian gold coins such as the India Government Mint Ashoka Lion coin, the obverse features the national emblem. Knowing the obverse helps buyers identify authentic coins and distinguish official government issues from private mints.

Gold ore is mined, crushed, and processed through a series of refining steps — including smelting and fire assay — to produce doré bars that are further refined into high-purity bullion. Understanding ore grades helps consumers appreciate why refining costs are factored into the final price of bullion and jewellery.

Also called an assay certificate, a purity certificate records the article's weight, declared and tested fineness, HUID, and the testing method used. In India, consumers can get any gold or silver item tested at a BIS-authorised centre and receive this certificate, which serves as legal proof of metal quality for resale, loans, or dispute resolution.

Quality marks on jewellery have been used for centuries as a form of consumer protection. In India, the BIS hallmark is the official quality mark for gold and silver articles, consisting of the BIS logo, a fineness number (e.g. 916 for 22K gold), and a HUID. Internationally, quality marks vary by country but always serve to guarantee that the metal has been independently tested.

In precious metals testing, quantitative analysis measures precise element concentrations. XRF spectrometry provides rapid quantitative results by measuring the intensity of fluorescent X-rays emitted by each element. Fire assay delivers the most accurate quantitative measurement by isolating and weighing the pure precious metal content. The results appear as the fineness number on a hallmarked article.

Gold refining in India is carried out by BIS-licensed refineries using methods such as aqua regia (chemical dissolution), the Wohlwill process (electrolytic refining), and the Miller process (chlorine gas treatment). Impure gold — often in the form of doré bars or old jewellery — is processed to remove base metals, yielding refined bullion of 99.9% purity or higher.

Rhodium is a rare platinum-group metal prized for its brilliant white lustre and exceptional hardness. In the Indian jewellery industry, rhodium plating is commonly applied to white gold and sterling silver pieces through an electroplating process. The coating gives jewellery a mirror-like finish but may wear off over time and need reapplication.

SGBs are issued in units of 1 gram with an 8-year tenure (early redemption allowed after 5 years) and pay 2.5% annual interest on the nominal value. The issue and redemption prices are based on the IBJA benchmark rate for 999-purity gold. Capital gains tax is exempt on maturity for individual investors, making SGBs a tax-efficient gold investment.

Derived from the Sanskrit 'tola' meaning weight, this unit was the base measure of mass in British India and remains a popular denomination for gold bars across South Asia. While India officially adopted the metric system in 1956, gold prices are still frequently quoted per tola in Zaveri Bazaar and other bullion markets. One tola equals exactly 180 troy grains or 3/8 of a troy ounce.

While still used for quick preliminary checks, touchstone testing has largely been replaced by XRF spectrometry for official hallmarking purposes due to the latter's superior accuracy and non-destructive nature.

A troy ounce is heavier than a regular (avoirdupois) ounce and is the global standard for trading gold, silver, platinum, and palladium. International bullion prices are quoted per troy ounce.

Ultrasonic cleaners work through cavitation — high-frequency sound waves generate millions of tiny bubbles in a cleaning solution that produce a powerful scrubbing action at the microscopic level. The method is safe for solid gold and platinum but should be avoided for plated items and soft gemstones like pearls. Hallmarking centres routinely use ultrasonic cleaning to prepare articles before testing.

Under-karating occurs when a jeweller sells an article labelled as, for example, 22K (916 fineness) gold when the actual gold content is lower. This was a widespread consumer concern in India before BIS made hallmarking mandatory in 2021. The hallmarking system, backed by independent assaying and HUID traceability, was specifically designed to eliminate under-karating.

Gold valuation in India follows a standard formula: Weight (grams) × Purity (fineness) × Current Gold Rate per gram. Purity is established through assaying methods such as XRF or fire assay. Jewellers, banks issuing gold loans, and certified appraisers all rely on valuation to set buy-back prices, loan amounts, and insurance values.

Vault storage plays a critical role in the bullion supply chain by providing insured, audited custody of precious metals under strict security protocols. In India, vault managers registered with IFSCA operate at GIFT City to store bullion for the India International Bullion Exchange (IIBX). Vault-stored gold also underpins financial products like Electronic Gold Receipts (EGRs).

When gold is cut, filed, soldered, and polished into finished jewellery, small amounts are lost as dust, shavings, and filings. Indian jewellers charge wastage as a percentage of the gold weight — typically 5–18%, depending on design complexity. Wastage charges are separate from making charges (labour) and are not regulated by BIS, so consumers should compare them across jewellers.

White gold achieves its colour by alloying pure gold with metals like palladium or nickel, and is usually finished with rhodium plating for a bright reflective surface. In India, white gold jewellery is hallmarked using the same BIS standards as yellow gold — an 18K white gold piece is stamped 750, confirming 75% pure gold content regardless of colour.

XRD works by directing X-rays at a sample and measuring the angles at which they diffract off the crystal lattice, producing a pattern unique to each material's atomic structure. While XRF identifies which elements are present, XRD reveals how those atoms are arranged — making it useful for detecting counterfeit alloys and verifying coating integrity.

XRF spectrometry works by irradiating the sample with high-energy X-rays, causing the sample to emit secondary (fluorescent) X-rays characteristic of each element present. It is the primary method used in hallmarking centres for rapid, non-destructive purity testing of gold and silver articles.

Yellow gold is the most popular form of gold jewellery in India, with 22K (916 fineness) being the overwhelmingly preferred standard for traditional and bridal jewellery. Its rich colour comes from pure gold's natural properties, enhanced by small additions of copper and silver. Unlike white or rose gold, yellow gold requires no plating and its colour does not fade over time.

Yield measures refining efficiency — for example, if 100 grams of scrap gold jewellery yields 88 grams of pure 24K gold, the yield is 88%. It is a critical metric for bullion refiners processing doré bars, old jewellery, and industrial scrap. Modern electrolytic refining achieves yields above 99.9%.

Established by Gujarati merchants in the 19th century, Zaveri Bazaar is the epicentre of India's bullion and jewellery trade. The market encompasses roughly 7,000 shops and serves as the primary wholesale hub from which gold jewellery and bullion are distributed to retailers across the country, significantly influencing domestic gold pricing.

BIS organises its hallmarking oversight through regional offices (e.g. ERO for Eastern Region, WRO for Western Region) that license and audit assaying and hallmarking centres within their jurisdiction. India has over 1,200 licensed hallmarking centres spread across all states and union territories. The zonal structure ensures local monitoring, grievance redressal, and coordination.