Trigon Party on a Diamond
A collection of trigons on the pavilion surface of a round brilliant-cut diamond. Photomicrograph by Isabelle Corvin; field of view approximately 2.0 mm.
Triangular-shaped markings known as trigons are common in natural diamond. These “birthmarks” formed during growth are signs of a diamond’s ancient origin deep within the earth. The trigons in the figure above form a striking cluster on the faceted girdle and extend into two of the lower girdle facets of a 1.01 ct natural diamond. Even through the cutting and polishing process, these trigons remained on the surface.
Although trigons are not exceedingly rare, the assortment of this many trigons grouped together provides a remarkable portrait created by Mother Nature. The perfection of a diamond is on full display in the angles, luster, and alignment of each trigon.
