Elongated Cushion Lab Grown Diamond Solitaire Ring on a Knife Edge Shank

Elongated Cushion Lab Grown Diamond Solitaire Ring on a Knife Edge Shank

An elongated cushion cut lab grown diamond in four claws on a knife edge shank, a band that is not round in section but tapers to a raised ridge running along its outer surface. The two flanks of the shank sweep up and open into a wide V beneath the stone, so the head sits on a fork rather than on a post.

A knife edge does something a round band cannot. A round shank presents a curved surface that returns one soft highlight wherever the light happens to fall. A ridged one presents two flat planes meeting at a line, and each plane reflects independently, so the band shows a bright line down its length and a shadow beside it. The result is that a very slim shank still reads clearly on the hand instead of disappearing, which is why the band here can stay this fine without the ring looking unfinished.

Center stone details

• Shape: Elongated cushion cut, soft rectangle with rounded corners
• Stone type: Lab grown diamond, IGI certified
• Carat weight: 2, 3, 4 or 5 carat, selected at checkout
• Color grade: E
• Clarity grade: VVS2
• Cut and polish: Excellent make, excellent luster
• Setting: Four claws on an open head carried on a split knife edge shank
• Certification: IGI certificate of the center stone is included at no extra charge

Band details

The shank is knife edged, meaning it comes to a soft ridge along its outer surface rather than being rounded. Below the head the two flanks separate into an open V that supports the setting from both sides. The inside of the band is rounded and smooth, so the ridge is only ever on the outside where it can be seen.

Metal options

Choose from 925 sterling silver, or 10K, 14K and 18K gold in yellow, rose or white. White gold is shown here and it gives the sharpest reading of the knife edge, because a white metal returns a cleaner highlight along the ridge. Yellow and rose gold soften that line and make the band warmer, which suits people who want the shape without the sharpness.

Ring size

This ring is available in a full range of US sizes. Select your size at checkout. If you are unsure of the size, contact us and we will help you measure at home before the ring is made.

Custom orders

We make every ring to order, which means the design can be adjusted. Ask us for a rounded shank instead of knife edge, pave along the ridge, a hidden halo, an east to west orientation, a different centre shape or a matching knife edge wedding band. Write to us through https://mapplegems.com/pages/contact and a member of our team will reply with drawings and a quote.

Frequently asked questions

What is a knife edge shank?
A band whose outer surface tapers to a raised ridge rather than being rounded. The two flat planes reflect light separately, giving the band a bright line down its length so a slim shank still reads clearly.

Is a knife edge uncomfortable to wear?
No. The ridge is on the outside only. The inside surface is rounded and polished exactly like any other band, so what touches the finger is smooth.

Why does the shank split under the stone?
Opening the two flanks into a V supports the head from both sides and lifts the stone slightly, which lets light in from underneath and keeps the setting stiff without adding metal.

What is an elongated cushion?
A cushion cut with a stretched length to width ratio, so the outline is a soft rectangle rather than a near square. It covers more finger for the same carat weight than a square cushion.

Is a lab grown diamond a real diamond?
Yes. A lab grown diamond has the same carbon crystal structure, hardness, refractive index and fire as a mined diamond. The only difference is that it was grown in a controlled environment rather than pulled from the ground.

Will I receive a certificate?
Yes. An IGI certificate for the center stone is included with every order at no additional cost.

Can a knife edge band be resized?
Yes. It carries no stones, so a jeweler can cut and adjust it and then re-establish the ridge when refinishing.

Why buy a lab grown diamond

A lab grown diamond gives you the same optical and physical properties as a mined stone at a far better price for the size and quality. Because the growth conditions are controlled, high color and high clarity stones like the E VVS2 used here are available in large carat weights that would be rare and costly in mined goods. It is also a traceable choice, with a known origin and no mining footprint.

Our services

• IGI certificate of the center stone included free with every ring
• Made to order in the metal, carat weight and size you choose
• Full range of US ring sizes
• Custom design and matching wedding bands on request
• Hand finishing and quality inspection before dispatch
• Secure insured worldwide shipping

About Mapple Gems

Mapple Gems is a fine jewelry maker based in Surat, India, a city that has cut and polished diamonds for generations. We design and build every piece in our own workshop, from setting the center stone to the final polish, which lets us control quality at each step and offer custom work that larger retailers cannot. We work only with lab grown diamonds and responsibly sourced gemstones.

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