A method was developed for determining points representative of the relationship between fragment size, grade, and potential recovery from a selected heterogeneous solid such as an ore. These points, when combined with economic data and the mean grade of the solid, are useful in establishing the range of fragment size at which separation (as for preconcentration of an ore by techniques such as sorting) may be effective. If the fragments are too large, in many cases adequately rich parts will not have been liberated; if too small, separation economics may be adversely affected, particularly in serial sorting operations. The method involves the use of a microscope to find data on the spatial relationships of the target phase in polished sections of a sample of the solid. A computer is used to select appropriate "base" particles of the target phase, to establish the size-versus-grade relationship in a radial distribution analysis, and to find the potential recovery in beneficiations aimed at a selected concentrated grade.
Trans. Soc. Min. Eng., AIME, V. 225, No. 1, March 1974, PP. 4-9