Mine Waters as a Source of Mineral Pigments
"Mine waters represent a well-known and serious ecological problem, but they can also be viewed as a source of valuable mineral raw materials. Their color range—from pale yellow (jarosite) through orange (schwertmannite) to black (hematite, goethite)—allows us to utilize their coloration and offers an intriguing connection between science and art. Preliminary findings suggest promising applications, such as oil-based paints or even fabric dyes," explained Zuzana Bártová from the Institute of Geotechnics SAS.
The main goal of the project is to develop a process for extracting pigments from mine waters. These pigments become the final solid product of mine water treatment, with high potential for commercial use. Although the project focuses on the abandoned mining site in Smolník, the new knowledge and research results obtained during the project will be applicable to other locations in Slovakia and abroad that are burdened by historic or ongoing mineral extraction.
"Depending on the elemental composition of the mine water, highly colorful precipitates can form, which can be processed into mineral pigments. Generally, the concept of extracting pigments for commercial use in this way is quite new. On one hand, we obtain raw materials for further use—such as pigments or commercially valuable metals and metalloids—while on the other hand, we address the environmental burden of the site," added Bártová.
In the pigment production process, iron-based precipitates—which are responsible for the typical orange color of mine waters—are first removed. This eliminates a visible part of the environmental burden, which then serves as the pigment itself. Bacterially derived pigments produced within the project have already been used for painting at the Faculty of Arts of the Technical University of Košice, receiving very positive feedback.
The use of living systems (such as the aforementioned bacteria) is fundamental to the process of biomining—a modern and eco-friendly approach to obtaining mineral raw
materials. Today, biomining is primarily used for extracting copper, nickel, and gold. It is a known fact that many rich ore deposits are nearly depleted (especially with respect to raw material self-sufficiency in the European region). Therefore, by using biomining, we can more effectively exploit ores with low metal content and especially the abundant old mining waste across Europe.
The MinePig project is titled "Secondary minerals from mine waters as a source of valuable pigments." It began in August 2024 and is planned for a two-year duration. This project opens the door to sustainable use of historical mining sites, supports the development of innovative approaches to raw material extraction, and creates new opportunities for connecting science, technology, and art.
Source and contact person: Zuzana Bártová, bartova@saske.sk