System and method for spectroscopy analysis of diamonds

The present invention relates to the a spectroscopic analysis apparatus (10) for distinguishing between colourless gems, comprising: a first light source (12) configured to emit a first primary beam (14) at a wavelength between 600 nm and 680 nm; a second light source (31) configured to emit a second primary beam (14') comprising ultraviolet light; a spectral dispersion device (22) arranged to collect the secondary optical beam (15) and to spatially disperse the secondary optical beam; a first photodetector device (24) arranged to collect the light dispersed by the spectral dispersion device (22); a second photodetector device (37) to detect visible light arranged in front of a second side of the gem,; a central processing unit (36) connected to the first and to the second photodetector device (24, 37), to the first (12) and to the second light source (31), the central processing unit (36) being configured to: establish that the gem is a diamond or is not a diamond; and if the gem is a diamond, establish that the gem is a type I natural diamond or a type II diamond.