A Note on the Analysis of Gilded Metal Embroidery Threads

Abstract

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Ion beam analysis of golden threads from Romanian medieval textiles

“…According to written sources [5,18,19], the cut strips are early times threads dated from the 13th century onwards, uneven in size and quality and of variable thickness, obtained by cutting a gilt metal sheet. The flattened strips, dated from the 14th century Fig.…”

“…Besides, EDS may sometimes give erroneous results. It was observed that the gold concentrations resulted for the gold coating and reported in previous publications are often too low depending on the high accelerating voltage used (usually 20-30 keV in practice), and thus incorrect [5,6].…”

“…Recently, in order to overcome some of these difficulties, more sensitive analytical techniques like AES, XPS, SIMS and laser-ICP/ MS have been used, and to our knowledge, few characterization studies by using IBA methods have been done so far [5][6][7][8]. Elemental analysis either on surface or in a depth profile by IBA methods are non-destructive and could provide unique information at the trace level sensitivity which make them ideal for the study of the very small and thin, possibly multilayered metal threads.…”

Extremely Thin Gold Layers on Gilded Silver Threads

“…We believe that most of the threads were manufactured abroad. Most analyses have been performed with a Jeol JSM-840A scanning electron microscope equipped with a Link-EDS unit for X-ray microanalysis at 20kV (SEM/EDS), occasionally also by Auger electron spectroscopy (AES) [1,2].…”

“…Material has been obtained from the church and Swedish collections, and SEM/EDS (scanning electron microscopy with energy-dispersive X-ray microanalysis) analyses have been undertaken. A first report was given at the 1999 ICOM-CC conference in Lyon [1], followed by a note on the analysis of gilded metal embroidery threads [2].…”