In the past, iron was obtained from ore in the area of southeastern Slovenia. They built smelting furnaces from clay and obtained iron with the help of coal and ore. Slag was also produced as a by-product. For an easier presentation and better interpretation of the archaeological remains from the archaeological site of Cvinger near Dolenjske Toplice, an experiment was carried out to reconstruct a prehistoric furnace based on the remains from that time. After gathering clay and ore, roasting the ore and grinding and sifting it, constructing a clay furnace and drying it, the iron extraction process was carried out. After a certain time of running the process, the furnace was opened and cooled down. This was followed by sampling of important parts of the furnace and different types of samples. The samples were analyzed using modern analytical methods. Methods used for sample analysis were scanning electron microscopy for microstructure analysis, scanning electron microscopy with energy dispersive x-ray detector for approximate chemical analysis, x-ray fluorescence and inductively coupled plasma coupled to optical emission spectrometer for quantitative sample analysis. The samples belonged to four major assemblages, clay and clay with slag, ore, charcoal and slag. The clay samples and samples of clay with slag have a layered structure, and the samples are rich in silicon, aluminum and oxygen. The ore is represented by samples that are rich in iron oxide and also contain some silicon. Raw coal is chemically composed of carbon and oxygen. The slag is represented by samples where we can see slag rich in iron oxides (heavy liquid slag) and slag rich in silicon and aluminum oxides (ceramic-rich slag). There is some emphasis on clay and the trend of iron content in clay samples. Finally, connections between experimental samples and archaeological samples and the literature are also explained.
|
