Most light sources are mixtures of various wavelengths of light. Many such sources can still effectively produce a spectral color, as the eye cannot distinguish them from single-wavelength sources. material’s ability to absorb certain wavelengths of light and reflect others is defined as its colour includes finish of Gloss, Semi-Gloss, Satin, matte, Sheen as seen in ASTM D1500, ASTM D1524, ASTM D6045, and ISO-2049.