Anita Quye

The natural constituents of historical textile dyes

The sources and structures of dyes used to colour Western historical textiles are described in this tutorial review. Most blue and purple colours were derived from indigo--obtained either from woad or from the indigo plant--though some other sources (e.g. shellfish and lichens) were used. Reds were often anthraquinone derivatives obtained from plants or insects. Yellows were almost always flavonoid derivatives obtained from a variety of plant species. Most other colours were produced by over-dyeing--e.g. greens were obtained by over-dyeing a blue with a yellow dye. Direct analysis of dyes isolated from artefacts allows comparison with the historical record.

‘Dragon’s Blood’ I—Characterization of an Ancient Resin Using Fourier Transform Raman Spectroscopy

Several resins generically known as ‘dragon’s blood’ from different botanical and geographical sources were characterised non-destructively using Fourier transform Raman spectroscopy. Genuine ‘dragon’s blood’ resin (Dracaena spp.) as found on Socotra Island was the probable source in antiquity. The spectra of recently collected Socotran resins from different sites were compared with fresh ‘dragon’s blood’ resins from Aden and Australia and a commercial source of Daemonorops draco from south-east Asia. All resin samples were freshly collected. A means of identification of the resins from their Raman spectra is proposed.

Raman spectroscopy of coloured resins used in antiquity: dragon's blood and related substances.

Dragons blood is a deep red resin which has been used for centuries by many cultures and much prized for its rarity, depth of colour and alchemical associations. The original source of dragons blood resin is believed to be Dracaena cinnabari from Socotra in Africa, but since mediaeval times there have been several alternatives from different geographical locations from the Canary Islands to the East Indies. Here, the Raman spectra of dragons blood resins from Dracaena draco Liliacae trees growing in several different locations bordering the Mediterranean and Middle East are compared with the resins from alternative botanical sources such as Daemonorops draco, Dracaena cinnabari and Eucalyptus terminalis, which all generically come under the description of dragons blood. Key vibrational spectroscopic marker bands are identified in the Raman spectra of the resins, which are suggested for adoption as a protocol for the identification of the botanical and possible geographical sources of modern dragons blood resins. The Raman spectra of materials, which are falsely attributed to dragons blood resin are also shown for comparison and identification purposes. Changes in the Raman spectra of genuine dragons blood resin specimens arising from simple processing treatment during the preparation of the resins for sale are also identified, which suggests a possible attribution characteristic for unknown samples.

Interpreting Lipid Residues in Archaeological Ceramics: Preliminary Results from Laboratory Simulations of Vessel Use and Burial

During the past four and a half years this group has been involved in a programme of development and testing of methods for the study of organic residues in archaeological ceramics. The analytical approach used is based on solvent extraction of powdered potsherds to release lipids absorbed in the ceramic fabric, with gas chromatography (GC) and combined gas chromatography/mass spectrometry (GC/MS) being used to characterise andquantify the individual components of the residues. Our most recent work has focused on an assemblage of more than sixty reconstructed vessels of Late Saxon/early medievaldate for which full or partial profiles were available. Analysis of potsherds sampled from different parts of these vessels, e.g. rim, body and base, have shown that different concentrations of lipid can exist in different parts of a vessel. This observation has important consequences for the sampling of potsherds for organic residue analysis. More significantly, these results indicate that the variation in the concentration of lipid in different parts of a vessel may reflect the way in which the vessel was used in antiquity. This paper discusses the results obtained from preliminary laboratory simulation experiments which have been carried out using replica vessels to provide supporting evidence for this potentially new approach to interpreting vessel use. Consideration will also be given to the possibility of using potsherds from these replica vessels in laboratory experiments aimed at simulating the decay of absorbed lipids during burial.

Characterisation of chemical components for identifying historical Chinese textile dyes by ultra high performance liquid chromatography – photodiode array – electrospray ionisation mass spectrometer

This research makes the first attempt to apply Ultra High Performance Liquid Chromatography (UHPLC) coupled to both Photodiode Array detection (PDA) and Electrospray Ionisation Mass Spectrometer (ESI-MS) to the chemical characterisation of common textile dyes in ancient China. Three different extraction methods, respectively involving dimethyl sulfoxide (DMSO)-oxalic acid, DMSO and hydrochloric acid, are unprecedentedly applied together to achieve an in-depth understanding of the chemical composition of these dyes. The first LC-PDA-MS database of the chemical composition of common dyes in ancient China has been established. The phenomena of esterification and isomerisation of the dye constituents of gallnut, gardenia and saffron, and the dye composition of acorn cup dyed silk are clarified for the first time. 6-Hydroxyrubiadin and its glycosides are first reported on a dyed sample with Rubia cordifolia from China. UHPLC-PDA-ESI-MS with a C18 BEH shield column shows significant advantages in the separation and identification of similar dye constituents, particularly in the cases of analysing pagoda bud and turmeric dyed sample extracts.

2',4',6'-trihydroxy-1-methoxyacetophenone monohydrate at 150 K.

The geometry of the title compound, 2-methoxy-1-(2,4,6-trihydroxyphenyl)ethanone, C9H10O5·H2O, is determined by the presence of an intramolecular hydrogen bond; the geometry of the benzene ring is distorted by a flanking carbonyl group.

Dyes and dyeing in the Ming and Qing dynasties in China: preliminary evidence based on primary sources of documented recipes

Colour has long held a special significance in Chinese culture, especially for textiles in the Ming (1368–1644) and Qing (1644–1911) Dynasties, the period when imperial handicrafts reached their production peak. This paper makes the first attempt to compare systematically historical Chinese records of textile dyeing to understand its practice. The paper presents research into the dyes and dyeing methods recorded in four important historical manuscripts of dye recipes from the periods of interest by examining the range and frequency of dyes and dyeing methods using statistical analysis methods. Issues such as the reliability of the historical resources of dyeing, the combination of raw materials, factors affecting the choices of dyes and dyeing methods and advances in dyeing are discussed. The findings of this research significantly promote the knowledge of textile dyeing for historical Chinese textiles research. They also have important implications for the understanding of world textile dyeing history.

The Dyer’s Handbook: Memoirs of an 18th-Century Master Colourist by Dominique Cardon

135 covering of the shield (Pylos) and strings to suspend the shield (Mycenae). In Chapter 5, ‘Textile and Stone Patterns in the Painted Floors of the Mycenaean Palaces’, Egan examines Mycenaean painted floors from megara in Pylos, Mycenae and Tiryns as imitations of stone pavements (Mycenae), textiles (Tiryns) and as a hybrid construction rendering an unrealistic combination of stone and textile surfaces (Pylos). The Pylian hybrids are interpreted as ‘being representative of the ability of man (perhaps imbued with divine power) to supersede the limits of reality and impose his will on his surroundings’ (p. 142). Chapter 6, ‘Sailing the Shining Sea: Maritime Textiles of the Bronze Age Aegean’, by Shaw and Chapin, discusses briefly a variety of maritime textiles and their possible representations in art, focusing on patterned depictions of ikria (stern screens), specifically the ones represented on frescos from the palace of Mycenae and West House, Akrotiri. A large part of this chapter (pp. 155–76) comprises excerpts from Shaw’s previous publications on ikria. Chapter 7, ‘String Lines, the Artist’s Grid, and the Representation of Textiles in Fresco’, gathers the excerpts from the earlier publications of Shaw, adapted for this book by Chapin. It surveys how the preliminary planning of frescos was executed using string impressions, for example, incisions of straight lines or sketching, and an artist’s grid. The latter was used exclusively to help in the rendering of units of the most complex textile patterns. Chapter 8, ‘Minoans, Mycenaeans, and Keftiu’, begins with a new introduction by Barber, but the majority of the content is taken from her seminal book Prehistoric Textiles (1991), and the chapter that discusses Aegean textiles in Egyptian iconography. The concluding chapter, ‘Observations, Summaries, Conclusions’, by Chapin, highlights the importance of the socio-cultural role of (patterned) textiles as ‘indicators of social status, ethnicity, age, and gender’ and markers of ‘power, wealth, and political authority’ (p. 255). Although a significant part of this book is a reprint of previously published research, by gathering together iconographic evidence of various categories of textiles, and discussing the limits and potential of an iconographic approach to textile studies, it serves as a valuable companion to the iconography of textiles in Bronze Age Aegean art for both archaeologists and textile researchers. What may be missing in this otherwise excellent publication is a more detailed and archaeologically based discussion on the technological possibilities of Aegean weavers of creating such textile patterns as represented in art.

Characterisation of oil and aluminium complex on replica and historical 19th c. Turkey red textiles by non-destructive diffuse reflectance FTIR spectroscopy

This work investigates historical and replica Turkey red textiles with diffuse reflectance infrared (DRIFT) spectroscopy to study the coordination complex between cellulose, fatty acids, and the aluminium ions that form the basis of the colour lake. Turkey red was produced in Scotland for around 150 years, and is held in many museum and archive collections. The textile was renowned for its brilliant red hue, and for its fastness to light, washing, rubbing, and bleaching. This was attributed to its unusual preparatory process, the chemistry of which was never fully understood, that involved imbuing cotton with a solution of aqueous fatty acids and then aluminium in the following step. Here we show, for the first time, a characterisation of the Turkey red complex on replica and historical textiles. The development of techniques for non-destructive and in situ analysis of historical textiles is valuable for improving understanding of their chemistry, hopefully contributing to better conservation and display practices. The results show the fatty acids condense onto the cellulose polymer via hydrogen bonding between the CO and OH of the respective compounds, then the aluminium forms a bridging complex with the fatty acid carboxyl. This contributes to an improved understanding of Turkey red textiles, and shows the useful application of handheld diffuse FTIR instruments for heritage textile research.