White marble sculptures from the National Museum of Roman Art (Mérida, Spain): sources of local and imported marbles. Eur J Mineral, 26, 2, 333-354. doi:10.1127/0935-1221/2014/0026-2369

ABSTRACT
This contribution reports the results of the archaeometric study of 51 marble sculptures and decorative elements from the capital of Roman Lusitania, Augusta Emerita (Mérida, Spain). These artefacts found on display at the Spanish National Museum of Roman Art comprise a representative record of archaeological pieces from different decorative programmes dated from the end of the 1st century BC to the end of the 2nd century AD.

A multi-method approach combining polarized-light microscopy, cathodoluminescence, X-ray powder diffraction, and stable C and O isotope analysis was applied to identify the marble provenance. The comparison of the results with the available databases confirms the use of different white marble varieties from the Estremoz Anticline (Portugal) as well as some Carrara and well-known marbles from Greece and Turkey. Another outcome of the study is the highlight of the most relevant parameters that serve to discriminate Estremoz Anticline marbles from other Iberian and classical marbles. In particular, the study is completed with a revision of the best parameters that may facilitate the Estremoz Anticline and Almadén de la Plata marble discrimination and an updated isotopic diagram for both white marble sources.