A method for measuring the quantity of a polymeric or pre-polymeric composition within a given volume that includes combining the polymeric or pre-polymeric composition with a plurality of microparticles having a non-ferromagnetic or non-ferrimagnetic core provided with a coating that is ferromagnetic, ferrimagnetic, or conductive, to form an admixture in which the microparticles are substantially uniformly dispersed throughout the composition. The microparticles have a detectable electromagnetic characteristic which correlates with the amount of the composition within a given volume. The electromagnetic characteristic of the microparticles is then measured to determine the quantity of the composition within a given volume.