Scientists from the University of Calabria in collaboration with Mónica Alvarez de Buergo, a Spanish researcher at the Geosciences Institute (IGEO) in Madrid, analysed white marble samples taken from an area now known as the Underwater Archaeological Park of Baia, near Naples in Italy.
According to a report by the Spanish Information and Scientific News Service (SINC), the region was a well-known Roman bath city between the first century BC and the third century AD. Roman emperors such as Augustus and Nero once frequented its luxury villas. Over time, however, coastal subsidence submerged the city, which now lays 5m below sea level.
The researchers sought to determine the source of the white marble featured in the villas, which was said to be one of the most valuable building materials used in their construction.
“When working with built cultural heritage, it is important to know where the marble originated so that its deterioration compared to reference materials can be determined,” Alvarez de Buergo explained. “That way, we can test whether treatments need to be applied, as well as identify which materials to use in the event that the original material needs to be replaced.”
Testing and comparing
Various microscopic and geochemical techniques were applied to the 50 samples, which were extracted from different surfaces in an area known as “villa con ingresso a protiro” (loosely translated as “villa with entrance to porch”). They were also compared against samples from eight varieties of white marble selected from some of the best Mediterranean quarries of the Roman period.
It was revealed that the Baia villa marble had been sourced from different quarries: Carrara in Italy; Proconnesos, Docimium and Aphrodisias in Turkey; and Thassos, Paros and Pentelicon in Greece. However, the researchers were unable to confirm the sources of five of the 50 samples.
“The variety and quality of the marble identified highlight the importance held by this area in the past, seeing as it yielded the best ornamental marble of that time period,” Alvarez de Buergo stated. She added that the new findings would also help historians determine the trade routes that were used during that era.
The researchers’ results have been published in the journal Applied Surface Science.