0.3 Carat Diamond Engagement Rings

Find your 0.3 ct diamond ring, with designs created to compliment and emphasise your diamond. Browse a number of styles before choosing your perfect, scintillating diamond.

Most rings shown with 1 ct 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 0.3 ct diamond rings

Weighing 60mg, a 0.3 ct diamond is a dainty choice. A round 0.3 ct diamond measures approximately 4.3mm in diameter.

A 0.3 carat engagement ring is fine and delicate looking. As the lowest carat weight your can choose from when creating your ring, a 0.3 ct diamond will have a subtle yet elegant charm, perfect for those with understated, minimalist taste. A 0.3 ct diamond ring might be a good choice for someone who has a very physical job and doesn't want their ring to get in the way.

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 0.3 ct Diamond Rings

How much does a 0.3 carat diamond ring cost?

As the lowest carat weight you can choose for your ring, you’ll find that a 0.3 carat diamond ring is the least expensive of potential diamond sizes, with the total cost starting around £1,250. A great quality 0.3 ct diamond typically costs £550 if it is a loose lab grown diamond, or closer to £750 for a loose natural diamond. The total price of a 0.3 ct diamond ring will have the additional cost of the ring setting itself, starting at £700.

It’s important to choose a diamond with top cut, colour and reasonably good clarity grades to ensure the diamond has an intense sparkle.

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

Is a 0.3 carat engagement ring small?

0.3 ct is on the smaller side of engagement rings - meaning they can look beautifully dainty and subtle. It is widely considered that an engagement ring should have a diamond that is no smaller than 0.3 ct. Classic engagement ring designs require diamonds equal to or larger than 0.3 ct. This means that a 0.3 ct diamond ring is just about the smallest size you can choose for your engagement ring, so it may appear small compared to other people’s rings, but that by no means diminishes its pure, sparkly beauty.

How big does a 0.3 ct diamond ring look?

A round 0.3 ct diamond will look around 4.3mm in diameter when viewed from above. This is quite dainty and on the smaller side, which will give the ring an understated elegance.

How big is a 0.3 ct diamond in mm?

A round 0.3 ct diamond is approximately 4.3mm in diameter, but the precise measurement of the diamond will vary depending on the depth of its cut. Other diamond shapes can appear larger in size, like the elongated oval, which has a much shallower cut. A 0.3 ct oval diamond is typically around 4.5mm in length, meaning it can look considerably larger than a round diamond of the same carat weight.

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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