Infrared spectrometry measures the characteristic frequency of vibration or rotation of compounds and molecules in a crystal lattice. These vibrations of molecular bonds in the crystal structure are induced by IR light transmitted through the sample or reflected from the surface. This results in the absorbance of specific IR wavelengths. Much like the UV-Vis spectrometer, this spectrometer gathers a wavelength absorbance spectrum. In gemmology, it is mainly used to identify OH compounds in gemstones and pearls.
The Gubelin Gem Lab possesses a Philips PU9624 FTIR and a Varian 640 spectrometer in the laboratory in Lucerne and a Perkin Elmer Spectrum One spectrometer for Off-Premise Testing.
