We present spectroscopic ellipsometric studies of bulk, boron-doped Si and Si-rich SiGe alloys for the free-hole concentrations from 2x10(19) to 4x10(20) cm(-3). We discuss the spectra of dielectric function, its inverse, conductivity, and the penetration depth of light. We study quantitatively the Fano-type resonance between the direct intervalence band transitions and the optically forbidden phonon line. The observed asymmetric lineshapes are influenced by the intervalence joint density of states and the finite width of the Fermi-Dirac distribution. They are found to be in very good agreement with a recent calculation of the final-state interactions in this situation by Belitsky and Cardona,