GIA Gem Refractometer (1949)

This compact gem refractometer, produced by the Gemological Institute of America in 1949, represents one of the earliest generations of GIA’s in-house optical instruments. Identical in design to the 1948 model, it features the same streamlined, space-conserving form that made it practical for both classroom instruction and professional gem testing during the post-war period.

The instrument is finished with a distinctive grey, heavy-duty protective coating engineered to resist surface scratching and environmental corrosion. This rugged exterior not only extended the working life of the refractometer but also reflected GIA’s focus on durability and reliability at a time when high-quality optical materials were difficult to source. Internally, the instrument incorporates GIA’s early precision prism and shadow-edge viewing system, forming the foundation for the modern refractometers that followed.

This is a museum archives and no unit is available for sale at this moment.