In this work the concept of "Granulometric Area" is introduced, which allows to establish a relationship between the granulometric curves and the compressive strength of the rock. After taking a series of rock samples, preparing them and executing crushing processes and evaluating the compressive strength of said materials, a relationship between these two parameters can be established and thus avoid permanently sending samples to the laboratory, allowing a significant savings in time and money. This relationship is presented in a graphic way, and easy to interpret in each study area, establishing the parameters for the identification of the rock treated and studied.