First volcanic rocks of the Calañas area, Central Sector of the Iberian Pyrite Belt, are felsic lavas that are included in a black shaly sequence at the bottom of the Volcano-Sedimentary Complex. This sequence is stratigraphically conformable with the underlying Phyllite-Quartzite Croup. Well-preserved palynomorph assemblages have been obtained from the shales. The miospore assemblages are assigned to the LN Biozone, indicating a latest Devonian age for the beginning of vulcanism. Palynological and isotopic results from Tharsis, Aználcollar and Neves-Corvo orebodies are similar, suggesting that the shaly sequence of Calañas area can be laterally correlated with the mineralized level. Presence/absence of sulphide ores could be explained by changes of facies related with basin paleogeography