Lab Notes Gems & Gemology, Fall 2013, Vol. 49, No. 3

Diamond with Unusual Laser Manufacturing Remnant


It is common to see laser manufacturing remnants on diamonds, especially stones in blocked form where the cut is not finished. Cutters may use lasers to show where to cut, which features to remove, or the desired shape. The remnants usually appear as straight or sinusoidal lines along the areas to be cut or removed.

A 3.59 ct Fancy Light brownish greenish yellow diamond recently submitted to the Carlsbad laboratory for examination displayed an unusual laser feature.

Figure 1. The 0.9 mm diameter laser manufacturing remnant on this diamond showed an interesting pattern. Photo by Troy Ardon.
The table of the blocked heart shape showed a laser remnant with an interesting pattern that resembled a watch face (figure 1). Unlike the typically linear remnants, this feature was circular and located directly on the table. The cutter’s intentions for placing the 0.9 mm diameter circle on the table are unclear, but it makes for a striking pattern rarely seen on diamonds, especially finished stones.

Tara Allen is a staff gemologist at GIA’s laboratory in Carlsbad, California.