Sapphire
As hard as ruby. One of the best coloured stones for an engagement ring.
Prices and what to check
Gemstone engagement rings
Which gemstones actually work in an engagement ring?
A coloured stone makes a ring personal. But an engagement ring gets worn every day for decades, and some stones handle that far better than others. Here's the honest verdict on nine of them, with real UK prices.
PK
Parth KananiOctober 2026 · 6 min read
In short: for a ring you'll never take off, choose sapphire, ruby or alexandrite. Aquamarine, morganite, emerald and amethyst are fine with some care. We'd think twice about opal and tanzanite for everyday wear. Whatever you choose, ask whether the stone is natural or lab-created, and how it has been treated.
Side by side
Nine stones compared
Hardness is on the Mohs scale, where diamond is 10. Typical price is the median across UK retail listings we checked in October 2026.
| Stone | Hardness | Everyday wear | Typical ring price |
|---|---|---|---|
| Sapphire | 9 | Everyday ring | £2,350 |
| Emerald | 7.5–8 | Ring, with care | £1,750 |
| Ruby | 9 | Everyday ring | £1,676 |
| Opal | 5.5–6.5 | Not for daily rings | £721 |
| Aquamarine | 7.5–8 | Ring, with care | £1,351 |
| Amethyst | 7 | Ring, with care | £922 |
| Morganite | 7.5–8 | Ring, with care | £574 |
| Alexandrite | 8.5 | Everyday ring | £1,219 |
| Tanzanite | 6–7 | Not for daily rings | £929 |
Made for every day
Hard and tough enough to wear for decades without special care.
Fine with some care
Good engagement stones if you take the ring off for the gym, gardening and heavy work.
Emerald
Hard but brittle, and almost always has inner marks. Choose a protective setting.
Prices and what to checkAquamarine
One of the better coloured stones for a ring. A popular engagement ring choice.
Prices and what to checkAmethyst
Good in a ring with some care. Strong sunlight can fade the colour over time.
Prices and what to checkMorganite
The same mineral family as emerald and aquamarine. Fine in a ring worn with some care.
Prices and what to checkWe’d think twice
Beautiful, but soft or fragile. Better as a special-occasion ring than one you never take off.
Gemstone or diamond?
Three things that are different
- Colour comes first. With diamonds you're grading the absence of colour. With gemstones, a rich, even colour is most of the value, and it's judged by eye, so see the stone in daylight.
- Treatment is normal, but must be disclosed. Most sapphires and rubies are heated; most emeralds are oiled. That's accepted. What isn't is a seller who doesn't tell you.
- There's no 4Cs to compare prices. Gemstone pricing is less standard than diamond pricing, so getting two or three quotes matters even more. Diamond buyers can use our price checker.
Want the stone for your birth month? Our birthstone finder rates all twelve months for everyday wear.
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Common Questions
What is the best gemstone for an engagement ring?+
Sapphire, for most people. It’s a 9 on the hardness scale, just below diamond, comes in almost every colour, and wears well every day. Ruby (red sapphire) and alexandrite are just as practical.
Do gemstone engagement rings cost less than diamond?+
Not always. A small sapphire in 9ct gold costs less than most diamond rings, but a fine 1–2 carat sapphire or emerald can cost as much as a 1 carat diamond. Price depends on the stone, its size and whether it has been treated.
Which gemstones should you avoid for an engagement ring?+
Soft or fragile stones, if the ring will be worn every day: opal, tanzanite, pearl, moonstone and turquoise. They scratch, chip or crack more easily. They’re lovely for occasional rings, earrings and pendants.
Are lab-created gemstones real?+
Yes. A lab-created sapphire, ruby, emerald or alexandrite is the same mineral as a mined one, grown in a lab. It costs less. What matters is that the seller tells you which you’re buying.
Do gemstones come with certificates?+
Valuable ones should. For a sapphire, ruby or emerald over about 1 carat, ask for a report from a lab such as GIA, SSEF, Gübelin or AGL. It should state whether the stone is natural and how it has been treated.