Unprecedented identification of chrome yellow pigment in 18th-century costumes from the Český Krumlov Castle Theater

Traditionally, dyes were used to impart color to textile fibers whereas pigments were used in paintings, manuscripts and other objects. Although pigments were applied onto textiles for surface decorations, e.g. in prints and inks, coloring cloth with inorganic pigments was rather obscure. In this study, we report an unprecedented occurrence and characterization of an inorganic yellow pigment in mid-18^th-century costumes from the Castle Theater in Český Krumlov, Czech Republic. Pb and Cr were detected directly in cotton and linen fabric by means of in-situ X-ray fluorescence. The elemental distribution in fibers was mapped using scanning electron microscopy with energy-dispersive X-ray spectroscopy, and the pigment identity was further confirmed as lead chromate using micro-Raman spectroscopy. The occurrence of this pigment, first synthesized in 1804, in much older artefacts was unexpected. This discovery uncovers unexplored pages of history, both the pigment and the theatrical costumes, providing evidence of the occurred intervention and dating the performed repairs to the mid-19^th century. Utilized in sleeve cuffs, attached to the original 18^th-century garment, and in a linen inventory label, lead chromate pigment represents not only the interest of Czech-Austrian aristocracy in the latest industrial advancements, but also their efforts to preserve cultural heritage, bearing the earliest testimony to restoration/renovation of secular garments in Europe and the first evidence of using the inorganic pigment for textile conservation in general. This communication underlines the importance of a complementary analytical approach in studying colorants applied to historical textiles and contributes to a deeper understanding of contemporary technology and pigment history.