9ct vs 18ct gold, and white gold vs platinum: which should you buy? (2026)

The short answer: 18ct gold for a special piece, 9ct gold for everyday wear and a lower price, and platinum if you want a naturally white metal that doesn't need re-plating. That's Goldsmiths' own advice, and the prices below show what each choice costs on the same ring.

Every piece here is sold new by Goldsmiths, a UK authorised retailer, at Goldsmiths' own price on the date shown.

How we wrote this

The purity figures come from the UK hallmarking standards, as published by the London Assay Office. The advice on colour, wear and care comes from Goldsmiths' own buying guides, and the prices are Goldsmiths' for designs it sells in more than one metal. We earn a commission if you buy through our links, which never changes the price you pay.

What the carats and hallmarks mean

A UK hallmark includes a compulsory millesimal fineness mark, which shows the purity in parts per thousand, according to the London Assay Office:

Goldsmiths explains that pure (24ct) gold is soft and easy to scratch, so it's mixed with other metals to make it more resistant, or to change its colour to white or pink.

What you pay: the same ring in three metals

Goldsmiths sells some designs in several metals with the same diamonds, which shows what the metal alone adds:

Prices are Goldsmiths' own on the date shown. On the ring, the diamonds are the same in every version, according to Goldsmiths, so the difference is the metal.

9ct or 18ct gold?

18ct gold is 75% pure gold. Goldsmiths' jewellery buyer describes it as "a wonderful option if you're looking for a special piece of jewellery, because it still has a high pure gold content and a lustrous look", and Goldsmiths calls it more resistant than pure gold, with a luxurious weight and sheen.

9ct gold is 37.5% gold. Goldsmiths says lower carats like 9ct and 14ct still share gold's famous shine, but are generally more affordable and even more hard-wearing, making them ideal for everyday jewellery.

Goldsmiths' advice: "If the piece is for a special gift or unique occasion, it's great to invest in 18k gold or platinum, whereas a 9k piece is excellent for wearing every day."

White gold or platinum?

Both are white metals, but they're made differently, according to Goldsmiths:

• White gold is an alloy: yellow gold mixed with nickel, manganese or palladium. 18ct white gold is about 75% pure gold, with a bright, lustrous finish. Unlike platinum, it needs re-plating every few years.
• Platinum is naturally pale grey and takes on a brilliant white colour and mirror-like shine when polished. Goldsmiths says it's rarer than gold, extremely strong (so it holds delicate settings well), denser and heavier, nickel-free and hypoallergenic, and doesn't need re-plating. It also takes on a duller patina over time, which Goldsmiths calls desirable.

Which to choose: platinum for a ring you'll wear every day for life and never want to re-plate; white gold for a brighter look at more price points.

Yellow, white or rose gold?

The carat is the gold content; the colour comes from what it's mixed with. Goldsmiths says rose gold gets its pink tones from copper rather than nickel, which makes it less likely to cause skin irritation than white gold. Yellow gold, it says, has "made a brilliant revival in recent years", and mixing metals is fashionable: white, yellow and rose gold can be worn together.

One exception: Goldsmiths advises against wearing gold of any shade next to platinum, because the denser platinum can wear the gold away.

Silver

Sterling silver is hallmarked 925: 92.5% silver. For silver gift ideas, see our Christmas jewellery gifts for her.