ROSA
Blue Sapphire & Diamond 18K White Gold Halo

A Royal Inspired Oval Blue Sapphire Engagement Ring

Few engagement rings carry the weight of history quite like the Rosa. Inspired by the iconic 12 carat blue sapphire first worn by Princess Diana and now worn by Catherine, Princess of Wales, this oval blue sapphire engagement ring brings royal style within reach. The Rosa captures the same unmistakable silhouette: a dazzling oval blue sapphire centre stone framed by a glittering halo of diamonds, set in radiant 18k white gold.

It is one of our most loved designs, and one of our most requested. The Rosa is the engagement ring chosen by those who want a piece with a story, a heritage and a presence that turns heads from the first moment it is worn.

A Chatham® Lab Grown Blue Sapphire at the Heart of Every Rosa

At the heart of every Rosa engagement ring sits a Chatham® lab grown blue sapphire, the benchmark for lab grown coloured gemstones. Chatham have been crafting world-class lab grown sapphires since the 1930s, and their stones carry the same Mohs hardness rating of 9 as a mined sapphire, the same chemical fingerprint, and the same deep, mesmerising blue. The blue sapphire is the gemstone of truth, faithfulness and the soul, which makes it a meaningful centre stone for an engagement ring with a story to tell.

The oval cut is the natural home for a blue sapphire. The elongated shape lengthens the finger, lends the centre stone real presence on the hand, and frames effortlessly within a halo. The Rosa is the definitive oval blue sapphire engagement ring in our collection.

An Exquisite Blue Sapphire and Diamond Halo Setting

The Rosa is a halo engagement ring at its most exquisite. The oval blue sapphire centre stone is encircled by a brilliant halo of conflict-free natural G/H SI diamonds, with the sparkle continuing along the shoulders in a dazzling pavé. Between the halo and the shoulders, the Rosa is set with 24 to 30 diamonds, the count scaling with the carat weight of your centre stone.
A diamond halo is more than decoration. The halo lifts the visual size of the centre sapphire, so a 1.08 carat blue sapphire reads closer to 1.5 carats on the finger, and it catches the light from every angle. The Rosa diamond halo engagement ring sparkles in a way few other settings can match.

Lab Grown Blue Sapphire vs Natural Blue Sapphire

A lab grown blue sapphire is a real blue sapphire. The chemistry, the hardness, the optical fire are all identical to a stone pulled from the earth. The only difference is where the sapphire was grown. A natural blue sapphire is mined. A lab grown blue sapphire is created in a controlled environment using the exact same elements, to the exceptional standards Chatham have set over decades.

Choosing a lab grown blue sapphire engagement ring means choosing extraordinary beauty at a fraction of the cost of a mined stone, with a guarantee of ethical and traceable origin. Every Rosa engagement ring is set with a Chatham lab grown blue sapphire as standard. If a mined natural blue sapphire is preferred, mention it when you get in touch and the team will quote accordingly.

Carat Weight, Stone Size and Metal Options

The Rosa oval blue sapphire engagement ring is offered in four centre stone sizes. Each size keeps the same elegant proportion between centre stone and halo, so the ring reads beautifully at every carat weight.

• 1.08ct / 7x5mm centre stone, delicate and refined, with a 24 stone halo
• 1.77ct / 8x6mm centre stone, the size shown in the main imagery
• 2.72ct / 9x7mm centre stone, bold and statement-making, with the full 30 stone halo
• 3.94ct / 10x8mm centre stone, made to order

Additional carat weights are available on request. The Rosa is also available in three metals. 18k white gold gives the purest reading of the blue sapphire and is the most direct tribute to the original royal engagement ring. 18k yellow gold lends a warmer, more vintage feel. 950 platinum is our most prestige metal option. The Rosa setting works beautifully with other oval coloured stones too, including rare padparadscha sapphire, pink sapphire and other Chatham lab grown gemstones.

Rosa Oval Blue Sapphire Engagement Ring

FAQs

Is the Rosa engagement ring inspired by Princess Diana's engagement ring?

Yes. The Rosa is our tribute to the Princess Diana engagement ring, now worn by Catherine, Princess of Wales. The oval blue sapphire centre stone, the diamond halo, and the proportions of the ring are all inspired by the original royal engagement ring. The main difference is the centre stone, which is a Chatham lab grown blue sapphire rather than a mined sapphire, at a fraction of the cost.

Are lab grown sapphires real sapphires?

Yes. A lab grown sapphire is chemically and optically identical to a mined sapphire, with the same elements, the same crystal structure, and the same hardness. The only difference is where the stone was grown. The Chatham lab grown blue sapphire used in the Rosa carries the same Mohs hardness rating of 9 and the same brilliant clarity as a mined sapphire.

What is a halo engagement ring?

A halo engagement ring features a centre stone surrounded by a ring of smaller diamonds. The halo amplifies the perceived size of the centre stone and frames it with additional sparkle. The Rosa is a classic halo engagement ring, with an oval blue sapphire centre stone encircled by a halo of conflict-free natural diamonds.

What wedding band fits the Rosa engagement ring?

The Rosa pairs beautifully with our Ember 2.20mm wedding band. The Ember sits flush against the halo and complements the proportions of the engagement ring. Other matching options are available, and the team can recommend the right wedding band based on the carat weight of your centre stone.

Can the Rosa engagement ring be made in yellow gold or platinum?

Yes. The Rosa oval blue sapphire engagement ring is available in 18k white gold, 18k yellow gold and 950 platinum. White gold gives the cleanest reading of the blue sapphire, yellow gold adds warmth and a softer, more vintage feel, and platinum carries our most prestige price point.

Can I buy the Rosa as a dress ring rather than an engagement ring?

Yes. The Rosa is a versatile design and works just as beautifully as a dress ring or right hand ring. The smaller 1.08ct centre stone is the most popular choice for a dress ring, with the larger sizes more often chosen as engagement rings.