Optical properties of sediment give 2 RGB colour combinations (Lab system for sediment color analyses) which characterize particular features of the mineralogical and geochemical composition of the sediment. The CIE (Commission Internationale d'Eclairage) L lightness parameter, partly correlated with CaCO3, organic carbon and oxides content, was measured with a Linescan V1.8 of Avaatech, in the visible spectrum, lens aperture of 8 mm, 5 msec time of exposure, and space resolution of 0.07m, at the University of Barcelona, Spain.