Infrared absorption spectra (in KBr) are given for three species ofBaltic amber: light and dark Succinite and Gedanite. Also the intensity of electron spin resonance signals was measured after grinding amber to 20-30mu particle size. This intensity, as compared with unground samples, was increased about 5 to 10 times, which confirms the hypothesis that free radicals are produced with grinding (by mechanical action). -- AATA