In FT – IR spectroscopy, a bundle of infrared light is aligned through a mirror system on a sample to be analyzed. The result of this course is a typical absorption spectrum which varies depending on the atomic groups and the molecules located inside the analyzed gems. Just like a fingerprint, the spectrum is typical for every kind of material, therefore, IR spectroscopy is often used in different scientific fields. In the gemological one, FT – IR spectroscopy is used for the identification of synthetic gems, the characterization of unrelated puffiness substances (such as oils and resins) located in the emerging splits and holes and is really useful for the I and II type diamonds recognition. The II type diamonds, azote – free, are often discolored using the High Pressure High Temperature (HPHT) method. When dealing with almost discolored II type diamonds, further in – depth analysis aimed at the identifying a possible treatment are needed. The laboratory is equipped with a range of accessory tools for reflectance and transmittance spectrum acquisition. It is also provided with a pill maker for the creation of pills made by pieces of the sample to be analyzed (3%) and anhydrous KBr (97%). Thanks to this technique, spectra can be acquired, even when a few milligrams of the to be analyzed material are available.