Understanding Different Types of Gold Karats

Gold karat (K) measures purity on a 24-point scale: 24K is 99.9% pure gold, 22K is 91.67% pure, and 18K is 75% pure. Higher karats mean more gold content and higher price; lower karats mean more alloy metals and greater durability. For Indian buyers, the BIS hallmark stamp (999, 916, 750) is the most reliable way to verify the karat of any gold purchase.

A karat measures how much pure gold is in a piece, out of 24 total parts. 24K gold is all 24 parts gold; 18K gold is 18 parts gold and 6 parts other metals. The formula is simple: purity % = (karat ÷ 24) × 100. Take 22K as an example: 22 ÷ 24 × 100 works out to 91.67% pure gold, which is where the BIS 916 hallmark figure comes from.

'Karat' (K) and 'carat' (ct) technically mean different things: karat measures gold purity, while carat measures gemstone weight, unrelated to gold content at all. In India, however, both spellings are commonly used to describe gold purity, and they mean the same thing in this context — which is why you'll see both "22 karat" and "22 carat gold" used interchangeably on the same jewellery bill, on a hallmark stamp, or in casual conversation with a jeweller. The confusion mostly comes down to regional spelling convention rather than any real difference in meaning: if a jeweller in India says "carat" while discussing gold, they mean the same purity scale as karat.

This is worth getting straight early, since every karat figure in this guide — from 24K down to 10K — follows the same 24-part scale.

Five karat types cover almost every gold product you'll encounter, from investment bars sitting in a bank locker to the everyday ring you never take off. Each one represents a different trade-off between purity, strength, and price, and the table below gives you the full picture before we walk through each one individually.

24K Gold — 100% Pure Gold

24K gold is the purest form of gold available, with 99.9% purity. The remaining 0.1% accounts for trace impurities that are practically impossible to eliminate at scale, even with modern refining — which is why 24K is sometimes marketed as "four-nines" gold rather than a literal 100%. Due to its softness, 24K gold is not typically used in jewellery that requires daily wear, since it dents and scratches far too easily to hold its shape over years of use. Instead, it's favoured for gold coins, bars, and other investment-grade products, where the goal is maximum purity rather than durability or intricate design work.

It carries the BIS 999 hallmark, and its value tracks the gold spot price closely, with minimal alloy dilution — which is exactly why it's the preferred form for gold as a financial asset rather than an ornament. Using the purity formula from earlier, 24K works out to (24 ÷ 24) × 100 = 100%, before accounting for the 0.1% trace impurity — the benchmark every other karat is measured against. If you're buying 24K specifically as an investment, instruments like Sovereign Gold Bonds and gold ETFs offer a way to gain the same price exposure without the practical concerns of storing and insuring physical bars or coins at home.

22K Gold — 91.67% Pure Gold (BIS 916 Hallmark)

22K gold contains 22 parts gold and 2 parts alloy metals — typically copper, silver, or zinc, with copper being the more common choice in India for the warmer, richer tone it produces. Known for its bright, radiant hue, 22K gold is commonly used in traditional and ornate jewellery like necklaces, bangles, temple jewellery, and wedding sets, and remains the most widely used karat for jewellery across India.

The BIS 916 hallmark is simply 916.6 rounded down — 916 parts gold per 1,000, or 91.6% purity, which is the same figure as 22K expressed as a fineness number instead of a karat. 22K strikes a workable balance between purity and the strength needed for complex traditional designs, though it's still noticeably softer than 18K or 14K, which is why heavily worn 22K pieces like bangles can show scratches and wear patterns over a few years of daily use. In Indian households, 22K jewellery is also commonly treated as a semi-liquid asset — bought during festivals, exchanged for updated designs, or used as loan collateral — which is part of why the purity distinction matters as much for resale as for appearance. This dual role, as both an ornament and a store of value, is a large part of why 22K has held its position as the default choice for generations of Indian buyers.

18K Gold — 75% Pure Gold (BIS 750 Hallmark)

18K gold contains 75% pure gold and 25% alloy metals, giving it a warmer, richer colour than 14K while remaining noticeably harder than 22K. That extra alloy content makes it the preferred choice for diamond and gemstone settings, since a harder metal grips stones more securely over years of wear — which is why most fine diamond jewellery, including engagement rings, defaults to 18K rather than 22K or 24K. It carries the BIS 750 hallmark, and it's common in white gold and rose gold jewellery, since the alloy blend needed to produce those colours fits naturally within the 18K composition.

Price-wise, 18K sits meaningfully below 22K per gram, purely because a smaller proportion of each gram is gold rather than alloy. That combination of lower cost, better durability, and colour flexibility has also made 18K increasingly popular for lighter, contemporary jewellery designs in urban India, alongside its long-standing traditional role in gemstone-set pieces. For a buyer weighing 22K against 18K for the same design, the practical question usually comes down to whether the piece needs to hold stones securely and survive daily wear, or whether it's meant for occasional use where the richer 22K hue matters more.

14K Gold — 58.3% Pure Gold

14K gold strikes a fine balance between durability and affordability. With 58.3% pure gold and 41.7% alloy metals — commonly copper, silver, or zinc — it offers excellent strength and resistance to wear and tear, making it a practical choice for everyday jewellery such as rings, bracelets, and watches that rarely come off. It's the dominant standard in the United States and much of Europe, where hallmarking conventions historically favoured a lower purity floor, and it remains far less common in India, where 22K is the cultural default for most jewellery purchases.

Because a smaller share of each gram is gold, 14K pieces cost noticeably less than an equivalent 22K design — often by a wide enough margin that it changes what size or design a buyer can afford at a given budget. That's part of why 14K has found a growing niche among Indian buyers shopping for Western-style or minimalist jewellery, even though it remains a small share of the overall market. The trade-off is a visibly paler yellow than 22K, since more of the metal by weight is alloy rather than gold, and some buyers find the colour noticeably less rich for traditional designs.

10K Gold — 41.7% Pure Gold

10K gold is 41.7% pure gold, the minimum purity legally allowed to be sold and marketed as "gold" in some countries, including the United States, where the threshold was set by federal trade regulation rather than any technical property of the metal itself. It's rarely found in the Indian market, where 22K and 18K dominate and cultural expectations favour higher purity, but where it does appear, it's valued for its high durability and noticeably lower cost per gram, often in smaller fashion pieces rather than traditional or bridal jewellery.

The trade-off is a visibly paler, almost brassy colour and a lower resale value, since less than half the piece by weight is actual gold content. For Indian buyers specifically, this lower gold content also matters if you're considering the piece as loan collateral: since gold loan value is based on the actual gold weight and purity pledged, a 10K piece will fetch a meaningfully smaller loan amount gram-for-gram than the same weight in 22K or 18K gold, which is one more reason it sees limited demand in a market where gold routinely doubles as a financial asset.

The trade-off across the table is consistent: a higher karat means more gold content and a higher price per gram, while a lower karat means more alloy and greater everyday durability. Neither end of the scale is objectively “better” — the right choice depends on whether you're prioritising purity or practicality for a given piece.

The Bureau of Indian Standards (BIS) certifies gold purity in India through a hallmarking system that's been mandatory for gold jewellery since June 2021. A genuine hallmark carries several distinct marks, and each purity level has its own three-digit code:

Alongside the purity code, hallmarked jewellery carries a HUID (Hallmark Unique Identification) — a 6-character alphanumeric code introduced in 2021 that's unique to that individual piece. You can verify any HUID through the government's BIS Care app, which is free to download and shows the registered jeweller, purity, and testing centre for that specific code.

Here's how to read a hallmark on a piece of jewellery, step by step:

• Step 1: Look for the small BIS triangular logo, usually near the clasp, inside a ring band, or behind an earring back — a jeweller's loupe or your phone's camera zoom helps.
• Step 2: Find the three-digit purity number next to the logo (999, 916, 875, 750, or 585) and match it against the table above.
• Step 3: Locate the 6-character HUID code, typically laser-engraved and quite small.
• Step 4: Open the BIS Care app, enter the HUID, and confirm it returns a match with the purity and jeweller shown on your piece and invoice.

If the verbal karat a seller quotes doesn't match the hallmark stamped on the piece, or the HUID doesn't verify in the app, treat that as a clear red flag before buying.

Gold's natural colour is a warm yellow. The colour variations you see in jewellery — yellow, white, and rose — come entirely from the alloy metals mixed in, not from any difference in karat.

• Yellow gold uses copper and silver alloys, which preserve and often deepen gold's natural warm tone. It remains the most popular choice for traditional Indian jewellery, where the richer hue is closely tied to cultural expectations around bridal and festive pieces.
• White gold is created using palladium or silver as the primary alloy, and is typically finished with a rhodium plating for a bright, silvery shine. That plating fades with wear and needs periodic re-plating every couple of years to keep its finish. Some older white gold alloys used nickel instead of palladium, which can trigger skin allergies in sensitive wearers, so it's worth checking the alloy composition if you have a known metal sensitivity.
• Rose gold uses a higher proportion of copper in the alloy mix, which produces its distinctive pinkish tint. A higher copper content gives a deeper rose shade, while a lower proportion leans closer to a subtle blush.

Karat and colour are independent choices: an 18K ring can be made in yellow, white, or rose gold, and all three would contain exactly the same 75% gold content — only the alloy recipe, not the purity, differs between them. Colour is a style decision and doesn't affect the gold's resale value, which is driven by karat and weight alone.

A common misconception among first-time buyers is that a higher karat is automatically the "better" choice. Higher purity means softer metal, which makes the jewellery prone to scratches and deformation. For a piece you'll wear daily, that softness is a real practical downside, not just a technicality — which is why the right karat depends entirely on what the gold is for, not on chasing the highest purity number available.

• Jewellery for daily wear: 18K or 14K gold. The added alloy content resists scratches and everyday knocks far better than 22K or 24K, especially for rings, bracelets, and watches worn constantly. The trade-off is a slightly lower gold content, but for a piece that gets bumped against doorframes and desks all day, that durability is worth more than an extra few percentage points of purity. 18K also holds gemstone settings more securely than softer karats, making it a practical choice for a daily-wear ring with a stone.
• Bridal or occasion jewellery: 2K gold, for traditional Indian designs. It offers the rich hue and cultural familiarity that bridal and festive pieces are typically expected to have, and its softness matters less for jewellery worn occasionally and stored carefully between uses. Many buyers also value 22K bridal sets as heirloom pieces passed down across generations, where purity and resale value matter as much as the design itself.
• Gold as an investment: 24K coins or bars for the closest possible tracking to the gold spot price, or 22K BIS-hallmarked jewellery if you want a piece that combines resale value with wearability. If you'd rather sidestep purity and storage concerns altogether, Sovereign Gold Bonds and gold ETFs offer a way to hold gold's price exposure without owning physical metal at all.

If your goal is pure investment, 24K gold is the best option. For jewellery that combines beauty and daily durability, 22K or 18K gold are ideal choices. For affordability and maximum resilience, 14K gold is a practical solution.

If your goal is pure investment, 24K gold is the best option. For jewellery that combines beauty and daily durability, 22K or 18K gold are ideal choices. For affordability and maximum resilience, 14K gold is a practical solution. In short: match the karat to how the piece will be used, not to the highest number on the price tag.

If you're weighing gold as part of a broader investment plan alongside jewellery purchases, Aditya Birla Capital's financial planning tools can help you think through how physical gold, digital gold, or gold-backed instruments fit your overall goals.