A system, method and computer program product is provided that enables measurement and determination of the relative material composition of ash content in a paper product. While materials in ash content, e.g., CaCaO.sub.3, Clay, and TiO.sub.2, have distinct x-ray absorption spectrum, by varying an X-ray gauge rapidly, measuring the absorption at each energy level and, comparing this to tables of fundamental physical parameters, the relative fractions of materials in ash content, e.g., CaCaO.sub.3, Clay, and TiO.sub.2, can be extracted. The relative weights of other constituent materials found in web or sheet paper products are additionally determinable.