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This work intends to distinguish resonant and nonresonant contributions to the nonlinear refractive index in ion doped solids using a two-color nonlinear technique. In this experiment, the alexandrite metastable excited state (2E) is populated via the 4T2 absorption band using a 514 nm pump beam (Ar+ laser), while the refractive index change is probed by a tunable dye laser, in resonance with the R lines (from ground to metastable transition at λ ∼ 680 nm). The absorption spectrum with the two characteristic R lines is also shown just for comparison of the spectra. Observations reveal that an absorption saturation signal follows the linear absorption spectrum.