One of the most precious colour pigments used in antiquity was red cinnabar – the colour pigment vermilion. A powder made from the red mercury sulphide (α-HgS) yields this bright red colour pigment. This raw material was expensive and was presumably imported into the Roman empire. The largest known deposits of cinnabar in the Mediterranean region are found near Almadén (Spain), Idria (Slovenia) and Monte Amiata (Italy), with smaller deposits in Turkey, Tunisia, France and Germany.
Extraction of cinnabar near Almadén goes back to the 6th millennium B.C. Although the smaller deposits near Idria and Monte Amiata were equally exploited by the Romans, written sources report that Almadén provided the greatest quantity of cinnabar imports into the Roman empire. Until now, the extraction of cinnabar in the Mediterranean region has not been fundamentally studied, and above all the contribution of smaller ore deposits has not been sufficiently examined. In recent decades, analyses of the origin of archaeological materials by means of mineralogical and petrographic investigations as well as analyses of elements and isotopes have been undertaken in order to enable the reconstruction of trade connections. While this type of investigation was focused for a long time on metal objects, recent years have seen an increase in the analysis of origin of archaeological glassware and pigments.
Particularly interesting in this context is the origin of cinnabar pigments from Ephesos, especially since small yet easily accessible cinnabar deposits are found in the vicinity of Ephesos (e.g., Çeşme peninsula). This leads to the question of whether these local resources were used in Ephesos or whether ores from far afield (e.g. from Almadén) were preferred for vermilion pigment.
The ore deposits that were mined in antiquity reveal marked differences in their lead isotope composition due to their differing geological ages and formation processes. The possibility therefore exists to differentiate between different sources of cinnabar raw material accessed during antiquity. For the vermilion pigments from Ephesos and the question regarding near and distant sources of raw material, the discussion in addition is opened up about the quality of the raw material as a motivation for trade, as well as about the specialisation of the workers and the ›outsourcing‹ of the health risks, which at that time were already known. The identification of non-local raw materials and the long-distance trade in cinnabar can therefore enrich our understanding of economic and political interactions in the Roman empire.