Endrei Walter szerk.: Textilipari Múzeum Évkönyve 8. 1995 (Budapest, 1995)

dr. Márta Járó: Manufacturing technique of gold threads and their imitations on museum textiles - chronology of the preparation of metal threads. Results of the scientific investigations

Very few historical data [50] and results of investigation are available about the metal threads made of copper plated with a noble metal, i.e. about the so called threads of Lyon, although we can find many threads of this type, especially among archeological findings. Researches are being carried out even now, I shall summarize the results obtained up to now. Gilt copper wire, as material used for making metal thread is mentioned in the contemporary sources known by me, for the first time in the work of Biringuccio, published in 1540. He describes that a thicker copper rod is covered with gold leaves, heated, and polished. A thin wire is drawn then from it [51]. The author does not mention that the gilt copper wire was also used in flattened form, as a strip. The Dictionnaire Universel du Commerce published in 1748 [52] and later sources write about copper wires plated at first with silver, then with gold, consequently covered with a double metal layer, resp. a variety of this, which had been flattened and then wound around a fibrous core. For gilding, the application of gold leaves is mentioned in each case. Copper-based threads have been analyzed by scientific methods only by very few scientists [53-55]. Unfortunately, because of the analytical methods used (the whole mass of the samples was analyzed) even these small number of data are rarely suitable to make comparisons. It can not be decided, for instance, on basis of the published results, whether the thread under discussion is made of a copper alloy, of gold-plated and/or silver-plated copper, etc. The earliest gold- and silver-plated copper thread (double coating) that we have analyzed, comes from a horse cloth used in the 16th century [56]. Test results of 17-18th century archeological metal threads made of copper plated with noble metal/s were published by Petraschek-Heim and by us [57, 58]. This type of thread has been used frequently even in the 19th century, according to the results of investigation [65]. The small number of data does not render possible yet to decide where did this type of thread come into use and which of the gilding methods has been applied first, whether the appearance of the doubly covered resp. plated copper wire can be connected to a workshop or to a precise date. This could be of great importance especially in case of the dating of graves from modern times.