Jewellery, in plain words

Glossary definitions

BIS Hallmark

The official mark of certified gold purity in India.

The BIS Hallmark is a set of four marks stamped onto gold jewellery by an assaying centre licensed by the Bureau of Indian Standards — the BIS logo, a karat indicator (916 / 750 / 585), the assaying centre identification, and the six-character HUID code. It guarantees that the metal's purity matches the karat declared by the seller — see 22K vs 18K for what those karat numbers mean. Every gold piece sold at Kishna Jewellers carries a BIS Hallmark.

Read the full guide on how to read a BIS hallmark →

Reference: Wikidata

22K vs 18K gold

22K is 91.6% pure gold; 18K is 75% pure gold mixed with stronger metals.

Karat measures the proportion of pure gold in an alloy. 22K (also written 916) is 91.6% gold — soft, deep yellow, traditional choice for Indian wedding jewellery. 18K is 75% gold — harder, holds gemstones securely, available in yellow, white, or rose tones. Both can be BIS-hallmarked.

22K vs 18K gold — at a glance

	22K (916)	18K (750)
Pure-gold content	91.6 %	75.0 %
Hardness (Vickers)	≈ 50 HV	≈ 125 HV
Colour	Deep yellow	Yellow / white / rose, depending on alloy
Best for	Bridal sets, mangalsutra, traditional pieces	Diamond settings, daily-wear, finer prong work
BIS hallmark mark	916	750
Resale value	Highest gold-content return	Lower gold-content return; design value depends on workmanship

Reference: Wikidata

Jadau

A traditional setting technique that embeds uncut gemstones into hot gold.

Jadau is a Mughal-era technique where uncut diamonds (polki) and gemstones are embedded into a soft 22K or 24K gold base. The gold is heated and the stones are pressed in by hand — no prongs, no glue. Jadau pieces are heavier, bolder, and significantly more labour-intensive than modern set jewellery. They are often paired with meenakari enamel work on the reverse.

Jadau vs Meenakari — two complementary techniques

	Jadau	Meenakari
Origin	Mughal India (Rajasthan / Gujarat)	Persia → Rajasthan / Gujarat
Technique	Uncut stones embedded in heated 22K/24K gold	Coloured glass enamel fused into engraved gold
Side of jewellery	Front (visible stones)	Reverse (decorative back)
Stones used	Polki (uncut diamond), emeralds, rubies	None — pigment is the decoration
Often paired with	Meenakari on the reverse	Jadau on the front
Time to craft	Weeks per piece	Days per piece (added to a jadau base)

Reference: Wikidata

Meenakari

The Persian-origin art of fusing coloured glass enamel into gold.

Meenakari is enamel work applied to the reverse side of jadau jewellery — vivid greens, reds, and blues fired into engraved gold. Originally from Persia, it travelled to Rajasthan and Gujarat. Meenakari turns a piece into a two-sided heirloom: glittering stones on the front, painted miniature on the back.

Reference: Wikidata

IGI certificate

An independent diamond-grading certificate from the International Gemological Institute.

An IGI certificate documents a diamond's 4 Cs — carat, cut, colour, clarity — measured by an accredited laboratory. IGI is the most common third-party grader for diamonds sold in India. The international alternative is the GIA certificate. Every diamond piece at Kishna Jewellers ships with an IGI or GIA certificate.

IGI vs GIA — diamond grading certificates

	IGI	GIA
Founded	1975 (Antwerp)	1931 (USA)
Most common in	India, Belgium, Middle East	USA, international high-end
Lab-grown grading	Yes — most widely used	Yes — separate report format
Includes 4 Cs (carat / cut / colour / clarity)	Yes	Yes
Laser inscription on girdle	Optional	Standard
Typical premium	Lower cost per stone graded	Higher cost; broader international acceptance
Available at Kishna Jewellers	Default for all certified diamonds	On request for any piece

Reference: Wikidata

GIA certificate

The most rigorous diamond-grading certificate, from the Gemological Institute of America.

GIA invented the modern 4-Cs grading system. A GIA-certified diamond is accompanied by a unique report number and laser-inscribed girdle, making it the international gold standard for diamond provenance. Where the IGI certificate is widely accepted in India, GIA carries the most weight outside it. Available on request for any diamond piece we craft.

Reference: Wikidata

Mangalsutra

A black-beaded sacred necklace worn by married Hindu women.

The mangalsutra is gifted by the groom to the bride at a Hindu wedding and worn for life as a symbol of marital union. Modern mangalsutra designs combine traditional black-bead strands with diamond pendants, BIS-hallmarked gold motifs, and regional motifs unique to Gujarat, Maharashtra, and the south.

Reference: Wikidata

Kada

A heavy, rigid bangle traditionally worn singly on the wrist.

A kada is a thicker, sometimes openable bangle — silver, gold, or platinum. Worn by both men and women. Sikh men wear an iron or steel kada as one of the five articles of faith. Women's gold kadas are often passed down as wedding heirlooms.

Reference: Wikidata

Kundan

Highly refined 24K gold foil used to set uncut stones into jewellery.

Kundan refers to the technique of setting uncut polki diamonds and coloured stones using strips of pure (24K) gold foil — which is exceptionally pliable. The foil is layered between the stone and the gold base; the stones are not glued or prong-set but mechanically held by the foil. Kundan setting predates jadau and is one of the oldest Indian jewellery techniques. The term is sometimes used interchangeably with 'jadau' but technically refers specifically to the foil-setting technique.

Reference: Wikidata

Polki

Uncut, unfaceted natural diamond — the original Indian diamond cut.

Polki is uncut, naturally formed diamond — used for centuries in Indian bridal jewellery long before modern faceted brilliant cuts existed. Polki diamonds appear less sparkly than modern brilliants because they retain their natural rough surface, but they have a soft, milky lustre that traditional jadau and kundan settings are designed to showcase. Polki is significantly more expensive per-carat than equivalent modern brilliant cuts because the rough must be hand-selected for clarity and natural shape.

Navratan

A nine-gemstone arrangement representing the planetary deities.

Navratan ('nine gems') is a traditional Indian jewellery composition combining nine specific stones — diamond, ruby, emerald, blue sapphire, yellow sapphire, hessonite, cat's-eye, coral, and pearl — each associated with one of the nine celestial bodies in Hindu astrology. Worn for spiritual balance as well as ornamentation. Navratan pendants and rings are particularly common as gifts and heirloom pieces.

Reference: Wikidata

Lab-grown diamond

A diamond synthesised in a laboratory — chemically identical to mined.

Lab-grown diamonds (also called CVD or HPHT diamonds, after the synthesis methods) are chemically and optically identical to mined diamonds — they are real diamonds, not simulants. They are graded on the same 4 Cs by the same labs (IGI and GIA both grade lab-grown), typically at 60-80% of the price of an equivalent mined stone. Resale value is currently lower for lab-grown but the market is shifting. For everyday or fashion pieces, lab-grown is increasingly the rational choice.

Reference: Wikidata

Karat vs carat

Karat = gold purity; carat = gemstone weight. Different units.

Karat (often abbreviated K, KT) measures the purity of gold as a fraction of 24 — 22K gold is 22/24 = 91.6% pure. Carat (abbreviated ct) measures the weight of gemstones — 1 carat = 200 milligrams. The two units are unrelated despite the spelling similarity. Indian jewellery typically uses 'karat' for gold and 'carat' for stones, but international writing sometimes uses 'carat' for both — context disambiguates.

925 sterling silver

Silver alloy with 92.5% pure silver content — the international standard.

925 silver (also called sterling silver) is the global standard alloy: 92.5% pure silver mixed with 7.5% copper or other metals for strength. Pure silver (.999) is too soft for most jewellery use. The '925' stamp is a global purity hallmark. Indian sterling silver pieces sold by registered jewellers also carry BIS hallmark marks. 'Silver' marketed without the 925 stamp may be a lower-purity alloy or silver-plated base metal.

Reference: Wikidata

Hallmark — gold vs silver

Gold uses BIS hallmarks; silver uses .925 marks plus optional BIS.

Indian gold jewellery is mandatorily BIS-hallmarked since June 2021 — see our full guide on how to read a BIS hallmark. Silver jewellery uses the international .925 (sterling) mark plus optional BIS hallmarking; the BIS silver hallmark scheme is voluntary as of 2026. For platinum, the Platinum Guild International (PGI) PT950 mark is the standard (95% platinum content). Always verify the metal stamp matches the karat / purity claim on the bill.

Read the full guide on how to read a BIS hallmark →

Reference: Wikidata

Vermeil & gold-plated

Vermeil is heavier, longer-lasting gold over sterling silver.

Both vermeil and gold-plated jewellery are base metals coated with a layer of gold. The differences: vermeil requires a sterling silver base + at least 2.5 microns of 10K+ gold (US standard) — typically 14K-18K. Gold-plating uses any base metal (often brass or copper) and any thickness of gold (often <0.5 microns). Vermeil lasts years with care; cheap gold-plating wears off in months. Neither is hallmarked under the BIS gold scheme — they are not 'gold jewellery' for purity-stamp purposes.

Reference: Wikidata