Knowledge about stone type, their applications, and sources contributes to archaeological studies regarding the region's economic condition and the supply of stone material. A particular challenge arises with certain stone types, such as the white Eastern Alpine marbles, highly valued in antiquity but with unclear distinguishing characteristics. Their extreme mineralogical purity (above 95% calcite), lack of specific structural and textural features, and wide geographical distribution in the Eastern Alps, complicate the differentiation of these marbles. Therefore, an effective method for distinguishing white marbles is necessary. Rocks in archaeological samples can be thoroughly examined using geological methods, which allow for a detailed understanding of their provenance. In our doctoral thesis, we examined three archaeological sites in the Celje region to achieve this goal: the three mosaics at Glavni trg, a tombstone from the Šempeter necropolis, and the remains of a Roman villa at Muzejski trg. The mosaic cubes (tesserae) were analyzed using mineralogical and geochemical methods. These tesserae are made of various stone types, including black, mainly laminated limestones, white miliolid limestones from the Karst Upper Cretaceous layers, red Upper Cretaceous-Pliocene limestones sourced from Istria and Northern Italy, yellow sparitic limestone likely from the Mediterranean ancient Triassic quarry in Tunisia (Chemtou), green andesite tuff from the Oligocene Smrekovec volcanism, and white rhyolitic tuff, presumably from the Italian Tertiary volcanism. The tombstone from the Šempeter necropolis is made of Middle Miocene Eastern Alpine marble. We aimed to distinguish marbles from two locations: Pohorje and Gummern (Austria), using geological methods. Additionally, we tested an unconventional method of fluid inclusion analysis, which offers rapid application and requires only a small amount of sample. However, this method presents a disadvantage due to the elevated risk of sample contamination. The results from the geochemical analyses were supplemented with existing literature on Pohorje, Gummern, and Treffen marbles. A discriminant analysis was applied, which identified possible sources for six archaeological samples, four from Pohorje and two from Treffen. This confirmed fluid inclusion analysis is a promising technique, particularly for distinguishing between Gummern and Treffen marbles. Suggestions for optimization were proposed, focusing on the time frame for solution mixing and measurements, along with the identification of areas needing further research. Based on mineralogical composition, the stones from the walls of Roman villa were tracked in the vicinity of the archaeological site and confirmed their local source. Gray recrystallized Triassic limestones were found on Grajski hrib in Celje and on the nearby hill Pečovnik. Volcaniclastic Triassic rocks are present along the Pelikan's path to Stari Grad and elsewhere around Celje. Additionally, rocks from the Smrekovec Oligocene volcanism series can also be found near Celje, and among others, Oligocene quartz tectonic breccias are present in the riverbed of the Savinja River.
|
