In the present investigation, a variety of strong and weak acids have been chosen for the bone decalcification process. Demineralization of dog cranial bone was carried out using 0.6 M concentration of either hydrochloric, lactic or citric acid. Optical characterization such as: reflectance spectra, tristimulus values and color parameters were employed and related to the degrees of demineralization. The CIE Labmethod was used to determine the L (luminosity), ÂaÂ (redÂgreen) and ÂbÂ (yellowÂblue) color values of the samples. The study has been extended to include the absorption and extension coefficients of the prepared samples. The variation in the optical parameters proved that the spectral behavior depended on the nature of the bone matrices which resulted from the phase composition of bone. The results indicate that the variation in the optical band gap was derived from TaucÂs extrapolation for the demineralizing acids. The data obtained are attributed to the differences of the demineralizing acids and their consequent actions on the products.