ABSTRACT: This research presents a case study of the use of specific energy measurements to map and model pit-scale faults in the Granite Pit at Gibraltar Mine, an open pit metal mine in British Columbia, Canada. Specific energy data were collected during drilling of over 100,000 blast holes. Specific energy is affected not only by the geomechanical properties of the rock being drilled, but also by drilling parameters, equipment wear, and drilling depth. The influence of these factors is partly mitigated by adjusting the dataset for drilling depth and applying a bilateral smoothing filter. The specific energy dataset is compared to known pit-scale faults, UAV photogrammetry, LiDAR models, and rock mass data from geotechnical drilling. Planar concentrations of low specific energy data are seen to correspond to the location of major faults. This is evidenced further by showing that specific energy increases with distance from faults, similar to rock mass quality.