C 1819 (OTTO) Cesium nitrate, GR 99.5% Cas 7789-18-6 - used in infrared spectroscopy, in x-ray phosphors, and in scintillation counters. C 1819 (OTTO) Cesium nitrate, GR 99.5% Cas 7789-18-6 - used in making optical glasses and lenses. C 1819 (OTTO) Cesium nitrate, GR 99.5% Cas 7789-18-6 - used in making optical glasses and lenses. C 1819 (OTTO) Cesium nitrate, GR 99.5% Cas 7789-18-6 - used in pyrotechnic compositions, as a colorant and an oxidizer, e.g. in decoys and illumination flares.