3 Carat Diamond Engagement Rings

Discover your perfect 3 carat diamond ring, with our curated selection of sublime ring designs, complete with your choice of exquisite 3 carat diamond.

Most rings shown with 1ct diamond

We’re here to help

We get it, you’ve never done this before.

That’s why we have diamond and design experts on hand, who are here to guide you through every step - from understanding what carat, color, cut and clarity mean, to designing the perfect ring.

About 3 Carat Diamond Rings

If you choose a 3 carat engagement ring, you’ll be choosing a ring that beautifully balances extravagance and contemporary taste. Considerably larger than the average engagement ring diamond size, a 3 carat diamond ring is big and sumptuous without looking over the top - suited best to super refined and stripped-back designs like solitaire rings and diamond band rings.

Ring Styles

Modern classics

You want your ring design to be timeless, and we get that. Our collection features rings that transcend trends, look great from every angle and are made to last a lifetime.

Try filtering your search by our core engagement ring styles:

Solitaire engagement rings
Diamond band engagement rings
Halo engagement ring
Trilogy engagement rings

Our Diamonds

Ethically sourced & certified

The modern way to buy loose diamonds for your engagement ring, with real 360 videos and advanced filtering. Whether you're looking for a lab-created or natural centre stone, find the perfect loose diamond from our responsibly sourced collection of certified diamonds.

Exquisite Craftsmanship

Made for you

Each Queensmith engagement ring is crafted to order, made just for you and your partner. We have an in-house workshop and production team that meticulously crafts your ring and finesses every detail until it passes our final quality control check. Our quality and finish is a cut above the rest.

As part of our commitment to you, we offer a Lifetime Care Package including manufacturer's warranty, free servicing, free resizing and free cleaning, fully inclusive with every ring made by us.

We've Got You Covered

In London
Certified Diamonds
Free UK
Free Resizing
40 Days

Frequently Asked Questions

Learn About 3ct Diamond Rings

How much does a 3 carat diamond ring cost?

A 3 carat diamond ring starts at around £9,700 - but the price varies massively depending on whether you choose a lab diamond or natural diamond.

A good quality 3 carat diamond typically costs £9,000 if it’s a loose lab grown diamond, or upwards of £150,000 if it's a loose natural diamond. The total price of a 3 carat diamond ring will have the additional cost of the ring setting itself, starting at £700.

You should be aware that diamond prices fluctuate, and this should be used as a guide price accurate at the time of writing.

How big is a 3ct diamond in mm?

A round 3 ct diamond has a diameter around 9.5mm. This can vary a tiny bit, depending on the cut ratios of the diamond - but you can use that as a ballpark size to help visualise how big a 3ct diamond will look on your finger. Elongated shapes, like oval diamonds, appear larger due to an increased spread of carat over the surface area.

How big is a 3ct oval diamond in mm?

A 3ct oval diamond measures around 11.05mm in length. This is 2mm lengthier than a 2ct round diamond. The length and proportions of a 3ct oval diamond will vary a little depending on how it has been cut - some ovals are longer and skinnier, and others shorter and more rounded.

Is a 3 carat engagement ring too big?

A 3 carat diamond engagement ring is large enough to stand out - and is considerably larger than the average engagement ring diamond size. Most people would agree a 3 carat diamond isn’t too big, particularly if it is set in a demure and refined ring style like a solitaire - but for others, a 3 carat ring might not be practical. Some people’s jobs may prevent them from wearing a large diamond, while it could suit other people’s lifestyles perfectly.

How popular are 3 carat engagement ring?

Only around 5% of people choose a 3ct engagement ring. This figure has increased significantly thanks to lab grown diamonds, which offer a much larger carat weight for the same price. Less than 0.2% of natural diamond engagement rings feature a 3ct diamond.

Customer Support

Do you have additional questions? No problem, let us help you through the process

Need help choosing the perfect ring?

Get in touch with our experts - we’re on hand to help.

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