In a press release sent to Lusa agency, the municipality points out that the existence of ancient Roman gold mines in the Central Region was not totally unknown, but also stresses that the results of this research project, which was directed by Consejo Superior de Investigaciones Científica - CSIC, show the true dimension of this complex.
Directed by Brais X. Currás and by F. Javier Sánchez-Palencia, the project already has results published in the journal Antiquity.
"The identification of a mining complex was carried out by means of aerial remote sensing, employing the analysis of aerial photography from the 1950s, but also by more modern ones, such as land clearing with LiDAR technology. The result is the documentation of an extensive set of mines, which places Lusitania as one of the main gold producing areas of the Roman Empire. These are mainly open-cast mines, which were worked with the help of water. In most cases, of these ancient explorations today only sterile materials remain, in the form of large piles of stone, known locally as 'conheiras'", is referred to in the note of the municipality.
It adds, "the mines are located mainly in the Tagus valley and its tributaries: the Erges, the Ponsul, the Ocreza and the Zêzere", and in the Zêzere a good part of the mines are located below the dams and can only be recognised in aerial photographs taken by the army in the 1940s.
"A large mining area has also been documented in the Alva river valley, until now almost unknown, and which houses one of the largest concentrations of Roman auriferous exploitations in all of Portugal," it points out.
The information also states that the excavations were carried out with the support of the local authority and were centred on the Covão do Urso and Mina da Presa mining complex.
"Excavations were carried out in the water tanks of the hydraulic network used in the operation. By this means, it was possible to demonstrate that the mines were in operation between the 1st- 3rd centuries AD. In addition, the study of the paleoenvironmental records preserved in the network made it possible to understand the changes in land uses derived from the beginning of gold mining," it is detailed.
Within the Penamacor mining complex excavations were also carried out in the Roman camp located next to Mina da Presa. The data obtained show that the camp's chronology is situated in the Julio-Claudian era, around the first half of the 1st century AD. At the time, the Lusitanian territory had already been conquered by Rome for a long time. Thus, the presence of the army would not be related to the conquest, but to the control of the territory and the exploitation of the resources.
This research began as part of a post-doctoral project of the Fundação para a Ciência e Tecnologia directed by Brais X. Currás at the University of Coimbra and was carried out with funding from the Spanish State's "Arqueología en el Exterior" projects.
Currently, research continues within the projects "AVRARIA. The gold of Hispania. Impacto territorial, económico y medioambiental de la minería del oro en el Imperio romano" and "AVRIFER TAGVS. Poblamiento y geoarqueología del oro en Lusitania (AuTagus3)".
The researchers plan to continue their excavations in the mining area of Penamacor, focusing on the study of the settlement linked to the mines.
From a geoarchaeological perspective, they will also seek to understand the geology of the gold deposits and the technology used to exploit them. They also intend to continue the study of the presence of the armies of Rome in ancient Lusitania and their relationship with gold mining.