GEMMOLOGIST (or Gemmologist)

The Gemmologist — also known as a Gemmologist — is a professional specialized in the study, identification, classification and evaluation of gems and precious stones. They possess in-depth knowledge of their physical, chemical and optical characteristics: refractive index, Hardness, density, inclusions, Fluorescence, all criteria that make it possible to distinguish a natural stone from a synthetic stone or an imitation, and to determine its origin and quality. Using specific instruments (loupe, microscope, refractometer, spectroscope), they analyze and authenticate stones, evaluate in particular the “4 Cs” of the Diamond (Carat, color, clarity, cut) and draw up certificates when necessary. In watchmaking-jewelry, the Gemmologist is involved in the selection and the Testing of stones intended for Setting (stone/jewel setting) of watches and jewelry, guaranteeing their authenticity and compliance. Their expertise, at the crossroads of science and the stone trade, protects both the manufacturer and the customer.

The discipline took shape in the 20th century with the creation of reference institutions: the Gemological Institute of America (GIA), founded in 1931, standardized diamond evaluation with the “4 C’s” scale, while Swiss laboratories such as the SSEF (Swiss Gemmological Institute), in Basel, specialized in the scientific analysis of colored stones for the watchmaking and jewelry industry. The Gemmologist notably distinguishes natural stones from synthetic stones and detects common treatments — heating, Oil impregnation, irradiation — which alter the color or clarity of a Gem without changing its nature. In the horological context, this expertise is essential for issuing certificates accompanying set watches. To learn more: Swiss Gemmological Institute (SSEF).