Potassium bromide is transparent from the near UV to long wave IR wavelengths. In IR-spectroscopy, solid samples which are difficult to melt or dissolve in any suitable IR-transmitting solvent, are analyzed by grinding with Potassium bromide powder, and pressing into a disc. This procedure has a high quality demand of the used potassium bromide. Potassium bromide Uvasol® is adjusted to a mean particle size of 150 μm. This is sufficient for the preparation of perfectly good pellets without the need for further pre-treatment and the associated risk of contamination. It also retains its powdery form over a period of years if stored in an air-tight condition. Its physical suitability for pelletising is checked by a special application test and its chemical purity established by full spectrum FT-IR analysis.