Hydrothermal activity during late Hercynian time resulted in epithermal silver-base-metal (Pb-Zn-Cu) vein formation in the eastern part of the Spanish central system. During the Hercynian orogeny, the central Iberian crust was thickened by compressional tectonics, heated, weakened, and subsequently overthickened by massive late Hercynian granitic intrusions. Subsequently, the central Iberian crustal welt underwent extensional collapse through lithosphere-scale, low-angle detachment faulting. The detachment systems evolved through tectonic denudation, isostatic rebound, and upward arching to define an extensional province much like the U.S. Basin and Range. Andesitic volcanism and hydrothermal activity occurred during extension, inducing epithermal-type hydrothermal convecting systems that leached, transported, and precipitated silver and base metals along fractures crosscutting the Hiendelaencina metamorphic core complex.