Jewelry Rendering From CAD: Show a Custom Ring Before Casting

Jewelry rendering is how a jeweller shows a client a custom piece before it exists: a photoreal picture of the ring or pendant, made from the CAD file or a sketch, so the client can say yes before the wax is printed and the metal is cast. We gave Visualizee one ring CAD screenshot and one pendant sketch, asked for the finished piece, then the same design in yellow, white and rose gold, platinum, sapphire and emerald. Each edit took 20 to 43 seconds. The claws, side stones and halo held on every variant. Below are the inputs, the words we typed, the times and credits, and the one thing it got wrong.

Quick answer: Screenshot the CAD in a clean shaded view, or photograph the sketch flat. Ask for one metal and one stone, and list what must stay: the claw count, the side stones, the band and the angle. Approve that render, then make every other metal and stone from it. Don't use the render for carat size, a new angle the CAD never showed, or proof that the piece can be cast and set.

Why Render a Custom Ring Before Casting

A client buying a custom ring is paying for something they can't see yet, and a grey CAD model doesn't help much. Most clients can't read a shaded viewport: the gold is grey, the diamonds are pale blue and the scale is missing. A photoreal render answers the question they are actually asking, "what will it look like on the day I give it", before the jeweller commits time and metal.

The render is also the cheap place to change your mind. Swapping yellow gold for platinum or a diamond for a sapphire after casting means a new casting or a new stone. Before casting, it is one more picture. Gift season makes this sharper: a client who wants a ring under the tree needs to approve the design now, while there is still time to print, cast, set and polish.

This is the jewelry version of colorways from one sample photo: one approved base, then variants that change one thing and keep the rest.

The Inputs: a CAD Screenshot and a Pencil Sketch

Each input is one picture of a design that hasn't been made yet. The ring is a CAD viewport screenshot of the kind Rhino or MatrixGold users export every day: an oval center stone in six double claws on a raised cathedral setting, one tapered baguette on each shoulder and a slim band that thins toward the bottom. The pendant is a pencil sketch on cream paper: a pear-shaped center stone with its narrow end at the bail, a halo of thirteen round stones and a round bail, marked 18 x 12 mm.

Both are generated pictures standing in for yours (the CAD at high quality, 79 seconds and 200 credits; the sketch at everyday, 20 seconds and 120 credits), made for an invented studio we called Corvell Atelier; a web search found no business by that name. With a real piece, take the screenshot from the angle you want the client to see, in a shaded display with the grid and gizmos on or off. The angle of that screenshot decides every render made from it.

All Renders at a Glance

Eleven edits from two inputs: ten passed and one slipped. Every metal and stone swap kept the six double claws, both baguettes and the band; the pendant kept all thirteen halo stones. The slip was size: a center stone asked to become 2.5 carats came back the same.

All 13 renders were 1,640 credits, about $3.41 on the $40 Pro plan; one everyday render is 120 credits, about $0.25. We checked each ring render for claws, side stones and band on full-size crops, and counted the halo stones on both pendants.

From CAD Screenshot to Approval Render

One request turned the grey CAD screenshot into a finished-looking ring, and it passed. The six double claws sit where the CAD has them, the two baguettes are in their channels, the cathedral rail is under the stone and the band thins toward the bottom, seen from the same three-quarter angle.

What we typed: "Turn the ring in this CAD screenshot into a photoreal product photo for a client approval, as if the ring had already been cast, polished and set. Keep exactly the design from the CAD model: the oval center stone and its proportions; exactly four double claw prongs (eight claw tips) holding it, in the same positions; the raised cathedral setting under the center stone; exactly two tapered baguette side stones, one on each side, in their channels; the slim band that tapers toward the bottom, with the same width and profile. Keep the same three-quarter viewing angle from slightly above. Change only: render the metal as polished 18k yellow gold, the center and side stones as colourless diamonds with real sparkle and facet reflections, remove the CAD interface, toolbar, grid and axis gizmo, and place the ring standing upright on a small matte off-white ring stand on a clean warm-grey seamless studio background, soft studio lighting with gentle reflections. No hands, no people, no text, no logos."

One honest note on that request: our text says four double claws, because that is what we had asked for when we generated the CAD stand-in, but the CAD came out with six. The render followed the picture, not the number. That is what you want. The CAD is the design; write the keep list from what the screenshot shows, and when the words and the picture disagree, the picture wins.

The render also replaced the CAD's simplified facet lines with a proper brilliant oval. That is a fair reading of "diamond", but it is the model's facet pattern, not your cutter's.

Four Metals From One Approved Render

Once the yellow gold render was accepted, three short requests made white gold, rose gold and platinum, and all three passed. Each one changed the metal and nothing else: same claws, same baguettes, same band, same stand, same light and camera.

The request is short because the approved render carries the design: "Keep everything in the reference photo exactly as it is: the camera angle and framing, the ring's shape and size, the oval center diamond, the six double claw prongs and their positions, the cathedral setting, the two tapered baguette side diamonds, the tapering band and its profile, the off-white ring stand, the warm-grey background and the lighting. Change only the metal: make the whole ring polished 18k rose gold."

White gold and platinum came out almost the same. We sampled the same area of the band in both and the average colour differed by a few points, platinum a touch warmer and greyer. That is close to the real thing: white gold is usually plated with rhodium, which, as GIA notes, even makes 14K and 18K white gold hard to tell apart by eye. What the client is choosing between those two is weight, wear and price, not the picture, so say that next to the render.

Sapphire and Emerald Centers

Swapping the center stone worked the same way and passed both times. A royal blue sapphire in yellow gold and an emerald in platinum kept the oval's shape and size, the six double claws and the two diamond baguettes.

The emerald needs a caution the picture doesn't give. The render shows a perfectly clean, brilliant-cut green stone. According to GIA, emeralds typically contain inclusions visible to the unaided eye (the trade calls them "jardin", French for garden), eye-clean stones are rare, and emeralds are more brittle than sapphire, which is one reason the emerald cut is the most common cut for them. A client shown this render could fairly expect a stone they will almost never get at their budget. Put the real stone, or a photo of it, next to the render before they approve.

Pendant From a Pencil Sketch

The sketch became a photoreal pendant in 24 seconds and passed. The pear's narrow end is at the bail, as drawn, and the halo has the same thirteen stones as the sketch. A second request made it rose gold with an emerald center, and the thirteen halo diamonds stayed.

We kept the pendant on a display bust rather than a neck on purpose. A bust shows the drop and the chain without inventing a person, and it is what most jewellers already use for product photos. The model did not draw the 18 x 12 mm on the paper into anything: the render has no scale, so the pendant could be any size on that bust.

The Gift Box and the Profile View

Two follow-ups turn an approval render into something to send in gift season. The rose gold ring went into an open green velvet box on a walnut table with fairy lights behind it, and it passed: same claws, same baguettes, same band.

The profile view is the one to treat with care. Asked for the same ring from the side, the model drew a convincing profile with the claws, the baguettes and the band all present. But the CAD screenshot never showed this side, so the height of the setting and the shape of the gallery under the stone are the model's guess. It looks right; we can't say it is right. For a profile the client will judge, export that view from the CAD and render it, as you did the first.

The Slip: a 2.5 Carat Stone That Didn't Grow

The one slip in this test is size. We asked for the center diamond as a 2.5 carat oval, with the band, claws and baguettes kept. The render kept everything, including the stone: its width is the same within a few pixels, and only its top edge sits slightly higher.

This isn't a bug to work around. As GIA puts it, carat measures weight, not size: one metric carat is 200 milligrams. A picture has no scale and no weight, so the model has nothing to measure a carat against. If the client wants to see a bigger stone, give it the size you want in millimetres relative to something in the picture ("make the center stone about a third wider, with the claws moved out to hold it"), and check the stone's real measurements in your CAD.

The Words You Say to Vizzy

In the app you don't need the long requests above. Upload the CAD screenshot and say what you'd say to a bench jeweller: "Make this ring look real: 18k yellow gold, diamond center and baguettes, on a ring stand. Keep the six double claws, the two baguettes, the band and this angle exactly." Vizzy writes the full keep list and the render request; read it before you render.

For variants, start from the render you approved, not from the CAD: "Same ring in platinum, nothing else changes." Then: "Same ring with a sapphire center, same size and shape." For a sketch: "Turn this pendant sketch into white gold with diamonds, on a velvet bust. Keep every halo stone where it is drawn." For the gift card: "Put the rose gold ring in an open green velvet box with warm lights behind it."

What It Can't Do

It shows what the finished piece could look like; it doesn't engineer, weigh or price it. These are the limits we hit and the ones your caster and setter will raise.

• It doesn't prove the piece can be cast or set. Wall thickness, claw strength, the stone seat and how the setter will reach each claw are not in a picture. They are in your CAD and your setter's hands.
• It doesn't know carat or size. A 2.5 carat request came back the same stone. Size comes from the stone's millimetre dimensions, not from a render.
• It invents views the CAD never showed. The profile view is plausible, not checked. Export every angle the client will judge.
• It shows ideal stones. The emerald came back eye-clean and brilliant cut. Real emeralds usually show inclusions, and lab-grown and natural stones of the same colour look alike in a picture.
• Colour on screen is not colour in the hand. Metal tones and stone colours are approximate; show the client real metal samples and the real stone before you order.
• It doesn't price the piece. Metal weight, stone cost and labour are not in the picture. Quote from the CAD.

How to Make a Client Approval Set

One approved render, one change per request, and the CAD kept as the source of truth. Every render in this test followed these steps.

1. Export one clean CAD view in a shaded display, from the angle the client should see, or photograph the sketch flat in daylight.
2. Count what defines the design in that picture (claws, side stones, halo stones, band shape) and write it into the keep list.
3. Render one metal and one stone first, and check claws and stones against the CAD on a zoomed crop.
4. Approve that render, then make every other metal and stone from it, one change per request.
5. Add the presentation shots (gift box, display bust) from the approved render, changing only the scene.
6. Export new angles from the CAD instead of asking the model to turn the ring.
7. Send it with the facts: stone measurements, metal, the real stone or a photo of it, and the note that the render is a design picture, not the cast piece.

For the same approach on other products, see 3D product visualization; the sketch to render walkthrough shows the steps recorded in the app on a building; and the AI rendering guide covers what AI rendering does well and badly in general.

Frequently Asked Questions

Can AI turn a jewelry CAD screenshot into a photoreal render?

Yes. We uploaded a grey CAD viewport screenshot of an oval engagement ring and asked for polished 18k yellow gold and diamonds on a ring stand, with the claws, side stones and band kept. It took 23 seconds at everyday quality (120 credits, about $0.25 on the $40 Pro plan), and all six double claws and both baguettes were where the CAD had them.

Can I show a client the same ring in different metals and stones?

Yes, make every variant from the approved render, not from the CAD again. From one yellow gold render we made white gold, rose gold and platinum, then a sapphire and an emerald center, 20 to 28 seconds each. Every one kept the six double claws, the two baguettes and the band. White gold and platinum came out almost identical, which is close to how they look in life.

Can a render show how big a 2.5 carat stone looks on the ring?

No. We asked for the center diamond as a 2.5 carat oval and got back the same stone, within a few pixels of the same width. Carat is a weight, and a render has no scale. Show size from the stone's millimetre dimensions in your CAD, or with a real stone or a replica on the finger.

Does a render prove the piece can be cast and set?

No. A render is a picture of the finished piece. It does not check wall thickness, claw strength, whether the stone fits the seat, or the metal weight and price. Those come from your CAD, your caster and your setter. Use the render for the client's yes on the look, and the CAD for everything that has to work.

Can I render a pendant from a hand sketch?

Yes. A pencil sketch of a pear pendant with a halo became a white gold and diamond pendant on a display bust in 24 seconds, with the same 13 halo stones as the sketch. A rose gold and emerald version made from that render kept the same 13 stones.

Can I use these renders on my website or Instagram?

Yes on a paid plan: Hobby, Pro and Max include a commercial license with no watermark. Free output is watermarked and for personal use only, so it is for trying the workflow on your own CAD or sketch, not for a listing.

One CAD File, Every Option the Client Asks For

One CAD screenshot became an approval render in 23 seconds, and that render became four metals, two coloured stones and a gift-box shot, each under 40 seconds, with every claw and side stone held. Size and unseen angles did not hold, so the render goes to the client next to the stone's measurements, the real stone and the CAD, not instead of them.

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Try it on your next custom piece. Upload the CAD screenshot or sketch and tell Vizzy the metal, the stone and what must stay: try Visualizee free, no card.