Wilhelm Kotarbinski’s sketches for the murals of St. Volodymyr’s Cathedral: A multi-analytical approach to the artist’s painting materials study

Wilhelm Kotarbinski (1848-1921) is an outstanding modernist Ukrainian artist of the late 19th and early 20th centuries who became widely known after painting murals in St. Volodymyr’s Cathedral in Kyiv. Kotarbinski’s sketches are an important part of his graphic heritage that plays a great role in understanding the artistic technique and his approach to creating murals. The purpose of the work was a comprehensive study of the painting materials of Wilhelm Kotarbinski’s four sketches for the murals of the Small Dome of St. Volodymyr’s Cathedral depicting seraphims and the introduction of the results into scientific circulation. The methodology was to apply a multi-analytical approach that included non-destructive analytical methods such as technical photography in different spectral ranges, microscopic examination, X-ray fluorescence analysis, and Fourier transform infrared spectroscopy. The presented work was the first comprehensive study of Wilhelm Kotarbinski’s drawings, which aimed to establish the artist’s technique and the technological characteristics of the paper support and to identify pigments in the paint layer. The results indicated that Italian-made paper was used as the sketches’ support, which characterised the same fiber and elemental composition. The paper support was made of cellulose obtained from annual plants, sized with animal glue, and contained gypsum and kaolin as fillers. The fluorescence characteristic of the sketch paper, the established elemental composition, and the comparative analysis of the degree of aging indicate that the paper was produced in the last quarter of the 19th century. It was shown that the execution technique of drawings consisted of the preliminary application of detailed underdrawings with a graphite pencil, including compositional lines. It was established that the sketches were painted with watercolors, and the pigments in the paint layer of the drawings were identified. The obtained results are an essential contribution to the existing body of knowledge about late 19th century artists’ materials and could be useful in researching and attributing studies of Wilhelm Kotarbinski’s graphic works