CT of a rough diamond for cut planning

Diamcad is a diamond company in the Antwerp diamond district, founded in 1989. The name stands for Diamond Computer Aided Design: Diamcad develops its own software to scan rough diamonds and to plan how to cut them, and its polishers turn high-value rough stones into certified polished diamonds. Diamcad has worked on famous stones such as the Lesedi La Rona.

The value of a polished diamond depends on its carat, clarity, cut and color. A rough stone can yield several polished stones, and the cut plan decides which ones: each planned stone should be as large as possible while keeping inclusions out of it or at least away from its most visible parts. Diamcad's planning software searches for the most valuable combination, and the stone is then split with a laser along the planned cuts.

The plan is only as good as the model of the stone. The surface of a rough diamond is often frosted, so it is hard to look inside it with optical methods. An inclusion that is missed or misplaced can end up in a polished stone and lower its clarity grade.

X-ray CT sees through the surface of the stone. Diamond is pure carbon, a light element that absorbs little X-ray radiation, so mineral inclusions containing heavier elements stand out against it. Explore the reconstruction yourself:

Slice view

Scroll through the stone slice by slice, zoom in, or switch to another axis. Inclusions show up as small bright spots.

3D view

Rotate the stone to see where the inclusions are inside it.