MINERALOGICAL CHARACTERIZATION OF BRAZILIAN KAOLIN ORE USING DIFFUSE REFLECTANCE SPECTROSCOPY

摘要

For most industrial minerals, the color is directly associated with economic value. In terms of physics, the principal property that defines the term "color" is the intensity of light reflected (or transmitted) by an object over the visible band, comprehended between 400 and 700 nm. This reflectance spectrum serves as the starting point for a variety of color-describing factors, the most common in the mineral industry being the brightness (TAPPI, 1977 and 1986) and the L~*a~*b~* system (HunterLab, 2008). Quality specifications for mineral products are usually based on these colorimetric parameters.