The use of laser technologies in the diamond manufacturing process can inadvertently leave marks on the finished diamond, according to the Gemological Institute of America.

Known as laser manufacturing remnants, these markings are unintentional characteristics of the manufacturing process, said Tom Moses, vice president of GIA Laboratory and Research. They do not represent a deliberate attempt to alter the diamond’s clarity grade or appearance.

Moses said that the GIA Laboratory is updating its method of reporting on the increasingly common process of laser technologies to “more clearly differentiate between a deliberate ‘laser treatment’ on a diamond and an ‘unintended laser manufacturing remnant.'”

The characteristics associated with laser manufacturing processes are surface grooves, surfacing-reaching marks, or completely internal marks, which may be associated with surrounding fractures, Moses says.

Previously, GIA reported internal remnants as “laser drilling,” surface remnants were called “laser grooves,” and diamonds with laser manufacturing remnants were said to have laser treatments.

These surface remains will now be covered in the GIA Laboratory’s assessment of polish, and internal laser remnants will show up in the report’s clarity portion, rather than being noted in the “comments” field. Meanwhile, intentional laser drilling, both internal and surface-reaching, will be reported as usual.

People who have a diamond accompanied by a GIA report with entries in the comments field noting “internal laser drilling” or “laser grooves” may resubmit those diamonds to the GIA Laboratory at no charge for a reevaluation of the characteristics and how they are reported.

For more information about this service, contact GIA Laboratory Customer Service at 760-603-4500 ext. 7590 in California or 212-221-5858 ext. 3724 in New York. Or e-mail labservice@gia.edu.

JCK