Measurements of the absorption coefficient of (111) crystal sections of&agr;-Fe2O3were made in the visibleand near infrared. Absorption peaks were observed centered at energies of about12000 cm−1and16000cm1.Reflectivity measurements on the&agr;-Fe2O3crystals were carried out in the30000 cm−1to400 cm−1range. Broad reflectivity peaks are found in the near ultraviolet at24500 cm−1and26000 cm−1, respectively.Very strong reflection peaks resulting from the lattice vibrations are present at energies smaller than700 cm−1.Several quite sharp peaks are found in the absorption spectra of the rare-earth iron garnets of Dy, Ho,Er and Yb in the10000 cm−1–13000 cm−1energy range. The circular dichroism of ytterbium iron garnet isdisplayed by means of absorption curves for the two senses of circularly polarized light.