ABSTRACT
The most important color system used in connection with instrumental color measurements Is the Commission Internationale de l’Eclairage system. The determination of color from spectral reflectance curves is based on the measurement of tristimulus values for each individual spectral color. Mixing and matching procedures for pigment-containing materials are largely an empirical task that is performed by professional color matchers with a wide experience in the visual examination of colors. Color is considered to be one of the most important properties in the identification and classification of minerals, but before the adoption of reflectance techniques its description depended solely on the individual observer’s color response. The results indicate that instrumental color measurements of ore minerals can be as sensitive as the visual color perceptions, but they are definitely more reliable and reproducible. Reflectance spectroscopy methods are widely used in this field for the measurement of color and for the quantitization of such factors as whiteness, brightness and gloss of papers.
