The identification of ore processing sites, whether in the preparation or smelting phase, is always a problem for anyone working on mining production. If the extraction sites can be located thanks to geological clues, topographical anomalies and the heaps they generate, the mineralurgical (sorting, crushing, grinding, washing) and metallurgical workshops can remain discrete, if not invisible on the surface. The implementation of surface geochemical surveys (using a portable X-ray fluorescence spectrometer and a differential GPS) provides a quantitative dosage in mass percentage at each measured point. A relative representation of these contents in space could be juxtaposed with an airborne LiDAR mapping. A part of the organization of the work can be outlined: the mining sectors are located on the hillsides where the sorting of ores rich in galena and sphalerite (high concentrations of lead and zinc in the soils) seems to take place, whereas the sectors at the bottom of the valley (rich in lead and poor in zinc) seem to be dedicated to the end of the process, probably to crushing, washing and metallurgy.