Abstract This paper reports the results of an archaeometric study of the marble from the Estremoz Anticline, Portugal. Thirty-four samples from eleven different locations were analysed petrographically. In addition, ten samples were selected for trace element and strontium isotopic analysis. The sampling was aimed at obtaining material from known ancient quarries and at establishing the overall petrographic and geochemical variation of the marble from the Estremoz Anticline. The main type of marble in Estremoz is a white(-veined), calcitic marble with an average maximum grain size between 0.81 and 3.50 mm. 87Sr/86Sr values of marble leachates range from 0.70850 to 0.70891 and are similar to the results for other Palaeozoic marbles of the Iberian Peninsula. In addition, a workflow is proposed for distinguishing Estremoz from non-Estremoz marble. For this, the Estremoz marble signature is compared to that of other known Roman marbles of the Iberian Peninsula (Viana do Alentejo, Almeria group, Malaga group, and Almaden de la Plata), as well as to that of the principal classical marbles from the Mediterranean (Carrara, Paros, Naxos, Pentelikon, Hymettos, Dokimeion, Thasos, Aphrodisias and Proconnesos).