Abstract: A method for performing a real-time estimation of the particle size distribution in the outer surface of a stockpile is provided. The method involves combining information about real-time stockpile volumes, rock parameters, and measures of particle size distribution obtained over a period of time which is long enough to provide consistent operational data points. The method involves receiving information about the stockpile volume and/or enough disperse level measurements to estimate the stockpile volumetric distribution which is later combined with particle size information. The information can be obtained from a sensor or a method which generates either a particle size distribution or size related parameters associated to an estimated distribution. Once all information is gathered, a particle size distribution, along with rock properties in the stockpile are obtained.