The development of the blast furnace metallurgy of the iron in Slovakia

Easily available sources of iron ore, the abundance of hydropower, and wood for charcoal were the prerequisites for the development of iron metallurgy in Slovakia. Since the 16th century, the bloomery process used in iron metallurgy has been gradually replaced by the blast furnace process. This new process was more economical, but it required extremely high investments. The steam engine replaced the unreliable water power in the blowing process, and coke replaced charcoal. Especially due to economic problems, the first blast furnaces in Slovakia started to be built about two hundred years later than in Western Europe. Despite the promising start, the installation of steam engines was lagging. A major drawback was the lack of road and rail networks combined with the absence of local coking coal. The introductory part of the paper compares chronologically the individual stages of the development of blast furnace production in Slovakia and abroad. Next, the paper presents comprehensive results of the analysis of samples of the slag found at 59 sites of extinct ironworks with a blast furnace, localised until now. The samples were analysed by metallographic, chemical, spectral (secondary and trace elements), and X-ray methods. In the past, these data were published with territorial restrictions and mostly in a language other than Slovak. The contents of secondary and trace elements in slag from individual sites using cluster analysis and also metallic iron content in slags categorised according to owners of the blast furnaces and the slag basicity are compared.