To assure consumer confidence, gemstone laboratories have long been issuing certificates which attest to a stone's authenticity. In recent years, certificates have also demonstrated proof of a diamond's origins and its non-involvement in internecine violence. But now a leading gem lab will also be issuing certificates for synthetic diamonds.

Hong Kong-based gemologists EGL Asia have begun to certify lab-grown diamonds by issuing two types of reports, both regular size and shortened reports. EGL Asia chief executive officer Joseph Kuzi says that the reports detail a rough or polished diamond's 4 C's, its measurements and proportions, finish, symmetry, cut grade and fluorescence. The reports use a yellow band at the top to easily distinguish them from reports from naturally harvested diamonds.

Kuzi says that the need for the reports has arisen in response to the increasing demand for synthetic diamonds in the Asian market.