The present work investigates the way in which cementing materials such as lime or Portland cement alter the quality of pigments nonmally used in coloring mortars for use in restoring stone construction of historic or artistic value. The colorimetric measurements indicated that both conglomerants diminish the chromatic capacity of the most pigments studied, with noteworthy tosses of saturation and in some cases, substantial variations in hire. The most serious incidents involved lend-vermilion and yellow-in both cases the hue shifting rewards the orange range. The compositional study of the material by X-mg diffraction (XRD) showed the decomposition of the compound chromophore, thereby accounting for its loss of color stability.