How to Design a Three-Stone Ring in Rhino

A three-stone ring is a conversation on the finger: a center that carries the story, two side stones that answer it, and a band that has to hold all three without looking busy. The easy mistake in CAD is treating it like a solitaire plus leftovers. The sides have their own size, their own seats, and they decide how wide the head can be.

This walkthrough builds one in RhinoArtisan, on Rhino: a princess in the center, two trillions on the sides, rose gold. About twenty minutes if you follow the video. Longer if you use it as the recipe for the next bridal order.

What you leave with: three stones that share one head, a prong basket that can be cast, a band that meets the setting cleanly, and a render in rose gold.

The reason this order of work matters is shop time. If you start with the band, you will reshape it twice. If you start with the center and the two trillions, the head is a decision and the shank is a fit. That is how you quote a three-stone without opening the file again tomorrow.

Place the center stone

Start with the princess. Square stones show every alignment error. Set the carat and the height on the finger before you invent the sides.

If the center is still “about a carat,” pick a real size and lock it. The trillions will be scaled to that square, not the other way around. A princess that moves later forces you to rebuild the basket and the gap between the three.

Set the side stones

The two trillions are not decoration. They close the width of the head and they point at the center. Place them so the long edge of each triangle faces the princess, with a hair of metal between, not a canyon and not a collision.

Watch them from the top and from the end of the finger. If a trillion sits too high, the three-stone reads as a crown. Too low, and the princess looks stranded. In the video this is the long middle section for a reason: once the three stones agree, the rest of the ring is structure.

Build the prong basket

The basket is what makes this a piece of jewelry instead of three gems floating on a band. In RhinoArtisan you build seats and shared metal so the princess and the trillions belong to one head.

Keep the walls thick enough to cast. Leave the prong locations implied, even if you dress them later. A pretty basket that cannot take a seat is a render, not a ring.

Check the underside. Three-stone heads hide thin spots between the center and the sides. That is where a caster will complain, and where a stone will sit on air.

Add the band

Now the shank. Finger size first, then the profile, then how it meets the basket. The band should arrive under the head, not crash into the side stones.

A three-stone is wider than a solitaire. If you copy a solitaire shank onto this head, the shoulders will pinch the trillions or leave two ugly gaps. Build the meeting after the stones exist, not from a library shank you liked last week.

Prongs and cleanup

This is the manufacturing pass. Prongs on the princess, prongs on the trillions, seats that match the cuts you placed.

Look from the side, from above, and from the finger hole. Cleanup is not polish for the render. It is deleting the leftover edges that will show in wax or in metal. If a prong covers a facet you wanted to see, move the prong, do not scale the stone.

Materials and render

Assign rose gold and diamond. The material step is late on purpose: you already decided the geometry. Rose gold will warm the princess and the trillions; it will also show scratches in the metal, so the surfaces have to be finished before you light the scene.

Put a camera on the three-stone from a three-quarter view so the square, the two triangles, and the band all read. If the sides disappear in the beauty shot, they are too small or too tucked. Go back to placement before you chase the lighting.

What to do next

Open the tutorial on YouTube and build the same ring once with your own center carat. Then swap the side cut (baguette, pear, half-moon) and keep the basket logic. The second time is when a three-stone stops being a special case.

If you want to run this on your own Rhino, start a 15-day trial or go to rhinoartisan.com.