Identification of dyes in coptic textiles from the museum of faculty of archaeology, cairo university

Abstract

High Performance Liquid Chromatography coupled to a Diode‐Array‐Detector (HPLC‐ DAD) is used to investigate samples which were extracted from ancient Egyptian textiles (4th–5th c. AD) of the Museum of Faculty of Archaeology, Cairo University. Madder is identified in several samples. According to semi‐quantitative results, which are obtained from HPLC peak areas measured at 254 nm, madder that is rich in purpurin and poor in alizarin is identified in samples which were treated (i) only with madder and (ii) with madder and either indigo/woad (Indigofera species and other/Isatis tinctoria L.) or weld (Reseda luteola L.). The madder dye used in these samples could have been originated from Rubia peregrina L. However, the possible use of Rubia tinctorum L. (or other plants of the Rubiaceae family) by the Egyptian dyers cannot be ruled out, particularly if methods were developed by the ancient dyers to affect and control the relative composition of madder dye. The HPLC peak area ratio of alizarin versus purpurin is very high (>2.2) for samples which were treated with madder (probably originated from R. tinctorum) and a tannin source. Finally, in some samples, only indigoid dyes (indigo/woad) are identified.