METHOD OF ANALYSING CUT PRECIOUS STONES Russian patent published in 2011 - IPC G01N21/87 

FIELD: physics.

SUBSTANCE: method involves recording optical density spectra of precious stones in the infrared range using a spectrometer fitted with a microscope working in reflection mode, performed as follows: the analysed cut precious stone or article with a precious stone is fixed in a holder with the platform up and perpendicular to the optical axis of microscope objective; the position of the sample is then chosen with focusing on the internal volume in the bottom part of pavilion such that the signal on the detector of the spectrometer is maximum, and spectrum of light passing through the sample and reflected from its surface is recorded. The background spectrum used can be the spectrum of the light reflected from a metallic mirror or spectrum of light reflected from the platform when focusing on the platform, or spectrum of light in transmission mode. The optical density spectrum from which the precious stone is analysed is calculated.

EFFECT: method is characterised by high rapidness and can be realised on standard infrared spectrometers fitted with microscopes.