An Old Mine Cushion with the Sides Left Open
By Clint Casmiro, Co-Founder, Smiro Studio, Toronto · Updated September 28, 2026
Short answer: On this 2.5 carat old mine cushion we put the claw prongs only on the north and south sides and left the east and west sides open. That lets the split shank open up and flow straight into the tulip basket, with a baby petal on the side profile, while the top view stays all about the old mine faceting.
I had so much fun designing this one. Here is why the prongs are where they are.
Read the video transcript
Custom rings you will never find at your local big box store. This ring features this gorgeous 2.5 carat, old mine cushion cut diamond. So you see the large facets in the middle of the stone. Very different than a traditional super facet of brilliant cut stone. And then it's set with these six claw prongs, but the claw prongs are only on the north and south side. We intentionally left the sides open because look at that split shank, opening up, flowing directly into the tulip baskets, added a little baby petal on that side profile. With this top view, the diamond is still the star of the show, really showing off this beautiful old mine cut.
What makes an old mine cut different
An old mine cut has large facets in the middle of the stone, very different from the many small facets of a modern brilliant. You get big, slow flashes instead of glitter. It is an antique cut brought back with modern precision. Compare it to other cushions in our cushion guide.
Why prongs on only two sides
Six claw prongs on the north and south hold the stone. With the sides open, nothing sits between the stone and the split shank, so the band can open right into the petals. It is a deliberate choice, not a shortcut.
The side profile
The split shank flows directly into the tulip basket, and a small baby petal sits where it meets the head.
The top view
The diamond is the star. No prongs crowding the sides, so the old mine outline and its facets show fully.
Want an old mine cushion set to show it off?
A free 30 minute video call with Clint or Karina. Bring a photo, a budget, or nothing at all.
Book a free callGet a 60 second estimateQuestions we get about this
What is an old mine cut diamond?
An antique style cushion cut with large facets in the centre, giving big flashes instead of glitter.
Is it safe to have prongs on only two sides?
Yes, on a cushion with six claw prongs. The prongs and basket hold it securely.
Are old mine cuts lab grown or natural?
Both exist. We will tell you plainly which a stone is.
How much does an old mine cushion ring cost?
A fully custom ring from us starts at about $4,000 USD, and most of the rings we build land between $4,000 and $5,000. Our Ready To Order settings start at $1,299 CAD, plus the diamond. The centre stone moves the price most: in September 2026 a 2 carat lab grown diamond ran about $2,500 CAD and a 3 carat about $2,700 CAD. Real numbers are in our cost guide.
Are old mine cut diamonds more expensive?
Antique cuts are less common, so a well cut one can cost a little more than a modern cushion of the same weight. Lab grown old mines have made them far more accessible.
Keep reading
Share
