Identification of white, grey and white and grey marbles used in the decoration of the architecture of Complutum (Alcalá de Henares, Madrid)

Abstract

We present the results of archaeometric analyses (petrography, optical microscopy (LPP, LPA), cathodoluminescence (CL) and isotope ratio mass spectrometry (IRMS) ?¹³C and ?¹?O) on samples of white and/or grey marbles from the architectural decoration of buildings in the Roman city of Complutum (Alcalá de Henares, Madrid). The marbles analysed, used in the production of slabs and moulded elements, come from Hispanic quarries, the Anticline of Estremoz (Portugal) and the province of Toledo, which allows us to confirm the majority use of Hispanic marbles — also from the limestones of Espejón — in the decoration of public and domestic constructions of this city in the inland of the Iberian peninsula.