Marquise and Round Lab Grown Diamond Open Shank Toi et Moi Engagement Ring in Silver, 10K, 14K and 18K Gold

Two laboratory grown diamonds on one ring that never quite closes. A marquise at one end of the band and a round brilliant at the other, the two ends passing each other rather than meeting. The French call it toi et moi, you and me.

At a glance

• Stones: One marquise cut and one round brilliant laboratory grown diamond
• Carat options: 2, 3, 4 and 5 carat, referring to the marquise
• Colour and clarity: E colour, VVS2 clarity on both stones
• Certificate: IGI, included free
• Setting: Claw set marquise and round on an open bypass shank
• Metals: 925 silver, 10K, 14K and 18K gold in yellow, rose and white
• Made: To order in Surat, India

Where toi et moi comes from

Napoleon gave Josephine a two stone ring in 1796, a pear sapphire and a pear diamond side by side, and the form has been called toi et moi ever since. It had a long run in the nineteenth century, disappeared for most of the twentieth, and came back in the last few years. The appeal is the obvious one: two stones, two people, one ring.

The open shank

Rather than joining into a closed circle, the band spirals past itself, one end rising to carry the marquise and the other curving beneath to hold the round. The gap is deliberate and structural, not a weak point: the two arms are thickened where they cross behind the finger.

Two different cuts on purpose

A marquise is long, pointed and dramatic. A round brilliant is the most symmetrical and the brightest of all the cuts. Pairing them rather than using two matching stones is what keeps the ring from looking like a mistake at the bench. The contrast is the design.

The points are guarded

The marquise has two tips, the thinnest part of any marquise. Each one sits inside a v claw that wraps around the edges either side of the point rather than pressing on it.

What laboratory grown means here

A laboratory grown diamond is a diamond. It is crystallised carbon with the same cubic structure, the same 10 on the Mohs scale, the same refractive index of 2.42 and the same dispersion as a mined stone. Ours are grown by chemical vapour deposition and high pressure high temperature methods, then cut and polished by hand. This is not moissanite, not cubic zirconia and not a simulant. A gemmologist testing it will read diamond, because it is diamond.

Metals

Choose 925 sterling silver, or 10K, 14K or 18K gold in yellow, rose or white. Rose gold is photographed here. On an open shank we would suggest 10K or 14K rather than 18K, since a band that does not close relies on the springiness of the alloy to hold its shape, and the harder golds do that better. White gold is rhodium plated and will want replating every one to two years.

Both stones arrive IGI certified

The marquise is graded by IGI, the International Gemological Institute, and the certificate comes with the ring at no extra charge. It states the carat weight, the E colour grade, the VVS2 clarity grade, the measurements and the girdle inscription, and confirms in writing that the stone is laboratory grown. The round brilliant is matched to the same E and VVS2 grade.

Made to order in our own workshop

Mapple Gems is a family run workshop in Surat, India, where most of the world's diamonds are cut and polished. The two arms are formed around your finger size so the stones sit where they should, which on a bypass ring is a matter of a degree or two of rotation. Allow two to three weeks for making, plus shipping.

Looking after it

Warm water, mild washing up liquid and a soft toothbrush. Brush underneath both stones. Do not pull the ring off by gripping the open ends, since that is how a bypass shank gets sprung out of shape over time.

Questions we are asked

What colour and clarity are the diamonds? Both are E colour and VVS2 clarity, on every metal and every carat weight.

Which stone does the carat weight refer to? The marquise. The round brilliant is scaled to suit it and is in addition.

Is the certificate really free? Yes. The IGI report for the marquise is included in the price on every variant.

Will a wedding band sit flush against it? No. An open shank has no straight edge for a band to sit against, so this ring is worn alone or with a band on the other hand. Many customers prefer that.

Can it be resized? Only slightly, because resizing changes where the two ends overlap. Please measure carefully and we will build to your size.

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