Department of Movable Heritage

DOMunder
Tussen 8 januari 2013 tot en met 9 mei 2014 is in
opdracht van initiatief Domplein door archeologen van
Erfgoed Utrecht archeologisch onderzoek uitgevoerd
voorafgaand aan en tijdens de bouw van de historische
attractie DOMunder. De missie van het initiatief Domplein
is de geschiedenis van het Domplein zichtbaar en
beleefbaar te maken voor een breed publiek. De basis
voor DOMunder bestaat uit de laatste grote opgravings-
putten XIX en XX die Van Giffen in 1949 heeft gegraven.
Deze liggen op de plek waar tot 1674 het middenschip
van de gotische Dom stond en waar de twee hoofdwegen
binnen het Romeinse castellum bij elkaar kwamen. Onder
en tussen de funderingen van de gotische Dom liggen de
resten van meerdere oudere kerken. Daaronder liggen de
resten van het Romeinse castellum. Het Domplein is een
wettelijk beschermd archeologisch Rijksmonument. Een
van de belangrijke uitgangspunten voor de realisatie van
DOMunder was dan ook dat de archeologische waarden in
en rond DOMunder niet zouden worden aangetast.

In 1635 or shortly thereafter, a Dutch ship was laden with all sorts of materials and products, mostly metals, but also textiles from the booming wool industries in both Flanders and Holland, a shipment of leather and exotic ivory. It was a ship of considerable size (at least 300 last) and departed from the Dutch Republic at a time of profound troubles. The Eighty Years’ War between the Republic and Spain was far from settled. War at sea was unremitting and intensifying, with Dunkirk privateers an unruly menace to Dutch shipping. Spanish rule in the southern
Low Countries was highly militarised, and constant campaigns were waged against it from the North. Central Europe was devastated by the Thirty Years’ War, which had entered a new phase through new alliances. The heavy and strategically valuable cargo of the Dutch ship was assembled from North and South, as well as from a range of places in central Europe. The ship departed for a destination that it never reached. It sank off the coast of Texel, where it was discovered 350 years later.
From 1985 to 1999 the wreck site and finds were subject to archaeological research, producing information on the ship, its setting and historical context as well as on the production and distribution of the individual shipments in the cargo, and informing us about the structure of early modern industry and trade, operating despite and because of the war. The present study, initiated by Wilma Gijsbers in 2010 and supported by the Cultural Heritage Agency of the Netherlands (RCE), the Maritime Archaeology Programme at the University of Southern Denmark (MAP-SDU) and the Netherlands Organisation for Scientific Research (NWO; a one-year
Odyssee grant), is the first to bring together all this evidence and evaluate it as a whole. Central to the study is the analysis of the ship and cargo assemblage as excavated, which is presented in Part 2 and 3 of this article. This is combined with an analysis of the discovery, its impact and the efficiency of fieldwork methodology in Part 1, and with reflections on the contribution the project makes to our understanding of production, trade and international relations in the specific
historical context in Part 4.

Due to the special conditions in the Bronze Age and Hallstatt Period salt-mines of Hallstatt, Austria, a large number of archaeological textile fragments, dated from 1400 to 400 BC, can be found. Textiles of good condition from these periods are quite unique. The fibres are identified as wool and most of the fragments still have colours i.e. yellow, green, olive-green, brown, blue and black. To obtain information about the dyeing techniques used in this period, dyestuffs analyses are performed by high performance liquid chromatography coupled to photo diode array detection (HPLC-PDA) and mordant analysis by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS). In addition, the condition of the textile fibres is assessed by SEM. The analyses revealed that all textiles were dyed with plant dyes and insect dyes. The yellow plant dyes and the red insect dyes are mordant dyes but the identification of mordants turned out to be difficult. SEM/EDS analyses of small uncontaminated areas on the fibre showed that the elements aluminium, iron and copper are present in many samples. These elements could originate from a mordant or from the mine. The condition of the fibres was assessed by the presence of the characteristic scales on the wool, tears, cuts and particles from the mine. It was found that a relation exists between the copper content of the fibres and their condition. Degraded fibres contain more copper. Black textile fragments which are most possibly coloured by iron gall-black show as well degradation phenomena.

The colorant behaviour of cochineal and kermes insect dyes in 141 experimentally-dyed and 28 artificially-aged samples of silk and wool was investigated using ultra-high performance liquid chromatography coupled to photodiode array detector (UHPLC-PDA), liquid chromatography electrospray ionisation mass spectrometry (LC-ESI-MS) and image scanning electron microscopy – energy dispersive X-ray spectroscopy (SEM-EDX). Partial-least squares discriminant analysis (PLS-DA) was then used to model the acquired UHPLC-PDA data and assess the possibility of discriminating cochineal insect species, as well as their correspondent dyed and aged reference fibres. The resulting models helped to characterize a set of 117 red samples from 95 historical textiles, in which UHPLC-PDA analyses have reported the presence of cochineal and kermes insect dyes.

Analytical investigation of the experimentally-dyed and artificially-aged fibres has demonstrated that the ratio of compounds in the insects dye composition can change, depending on the dyeing conditions applied and the type of fibres used. Similarities were observed when comparing the UHPLC-MS and SEM-EDX results from the dyed and aged references with the historical samples. This was verified with PLS-DA models of the chromatographic data, facilitating the classification of the cochineal species present in the historical samples. The majority of these samples were identified to contain American cochineal, which is in agreement with historical and dye identification literature that describe the impact of this dyestuff into European and Asian dyeing practices, after the Iberian Expansion in the 16th century.

The analytical results emphasize the importance of using statistical data interpretation for the discrimination of cochineal dyes, besides qualitative and quantitative evaluation of chromatograms. Hence, the combination of UHPLC-PDA with a statistical classification method, such as PLS-DA, has been demonstrated to be an advisable approach in future investigations to assess closely related species of natural dyes in historical textile samples. This is particularly important when aiming to achieve more accurate interpretations about the history of works of art, or the application of natural dyes in old textile production.

As the previous chapters [of Transformation through Destruction: a monumental and extraordinary Early Iron Age Hallstatt C barrow fro the ritual landscape of Oss-Zevenbergen, edited by D. Fontijn, S. van der Vaart & R. Jansen] demonstrate, the Early Iron Age bronze studs from Zevenbergen, mound 7 are among the most important finds of the excavation, and the procedure followed for their conservation is special. In chapter 7, it was argued on the basis of find context that these studs were affixed to some organic material, probably wood or leather. It was also observed that the objects display re- markable colours. Several questions still remain, which this chapter will address:
1. What is the composition of the bronze studs, and can the different colours be
explained on basis of these results?
2. What is the most plausible prehistoric production process of the studs?
3. Does the conservation treatment influence the analyses?
To answer the first research question, an assembly of 66 fragments is available for closer study (section 9.1.1). These fragments include intact studs as well as dis- torted and broken pieces of bronze once belonging to multiple intact studs. The objects selected show a variety of colours (Fig. 9.1): brownish-black and white with green spots and occasionally red grain-like structures. In section 9.2, the results of several analytical techniques that give insight into the composition of the studs are presented and discussed.
The second question does not necessarily need analytical equipment in order to be answered. This chapter will propose several options for production, based on close visual study of the available studs and literature. A reconstruction of the process is described in section 9.3.
During the use of certain analytical techniques, information about the conser- vation treatments will be gained. The influence of the application of the treatment on the bronzes therefore can be evaluated as well, which is done in section 9.4.

The preservation of woollen textiles in the prehistoric salt mines of Hallstatt is a lucky chance for the study of prehistoric textile dyeing. The Hallstatt textiles collection of the Department of Prehistory at the Natural History Museum Vienna shows the creativity of the prehistoric people. Already in the Bronze Age, the main materials for wool dyeing had been discovered: Woad served as indigo plant for dyeing blue, and rhizomes of Rubiaceae for dyeing red. Plants provided dyes for yellow and tannins for black. Out of the 12 analysed samples from 11 Bronze Age textile fragments, 9 are dyed and 3 are probably dyed. In textile fragments of the Hallstatt Period a greater number of yellow dyes were detected pointing to the use of plants which up to now had not been known for the Bronze Age. Green was dyed through combining woad blue with yellow. The palette of reds seems to be expanded through the use of dye insects and lichens. Frequently, woad blue was combined with other dyes and tannins to achieve dark blues. They went perfectly together with clasps, belts and necklaces made of shiny bronze. Out of the 67 analysed samples from 49 Iron Age textile fragments, 42 were dyed, 8 were probably dyed and 17 probably not dyed.

In 2014, a large collection of textile fragments was found in a 17th-century shipwreck (named BZN17) that had sunk in the Wadden Sea, near the island of Texel, The Netherlands. Captured in a time capsule for centuries, this collection represents a unique example of 17th century fashion, comprising over 150 textile fragments, including costumes, parts of costumes and interior textiles. Although buried for centuries, they are in remarkably good condition, which might be related to the archaeological environment and the high quality of the fabrics. Indeed, these are almost entirely made of silk (except one woollen carpet), and embroidered or woven with metal thread. The most striking characteristic of this collection is the well-preserved deep red colour displayed by many of the textiles.
To understand the origin and function of these textiles, as well as their state of conservation for future preservation strategies, it was important to characterize their materials. Hence, a group of 12 objects was selected for evaluation with ultra-high performance liquid chromatography with diode array detector (UHPLC-PDA) and a scanning electron microscope coupled to an energy dispersive x-ray spectrometer (SEM-EDX).
With UHPLC-PDA, coccid insect dyes were identified as the main colorants on the textiles. However, the ratio of their dye compounds seems to have been affected by the maritime archaeological conditions: dcII and flavokermesic acid were not reported in any of the textiles; and an unusually high kermesic acid equivalent was detected, in relation to the major compounds kermesic and carminic acids. Even though American cochineal and kermes could be possibly attributed in some cases, these results substantially hinder the precise identification of the insect sources. Besides these, madder was often found mixed with the insect dyes or in textile parts that are not directly visible on the costumes.
The evaluation of the fibres with SEM-EDX indicated that some fibres show evidence of microorganism attack, and that the majority has preserved their flexibility; although those from fabrics of lower quality (e.g. lining) are more friable. On the metal threads, silver sulphide crystals were observed, and these correspond to the degradation product of silver. Also, gold was detected on few threads, which indicates that they were probably gilded. Due to the corrosion of silver, most gold particles could have been lost in the maritime environment.
While the provenance of these textiles, and the ship that carried them, is still under investigation, the analytical results obtained undoubtedly prove that a very rich finding has been unearthed. Nevertheless, the archaeological conditions certainly had a preponderant influence on their original appearance and this deserves future research.

In de zomer van 2014 is een grote collectie 17de-eeuws textiel gevonden in een scheepswrak bij Texel. De collectie is overgedragen aan Museum Kaap Skil te Texel en is later naar de rechtmatige eigenaar, de Provincie
Noord-Holland, gegaan. In het najaar van 2015 is contact gezocht met de Universiteit van Amsterdam, conservering en restauratie van cultureel erfgoed (UvA-C&R) om mee te helpen met het beheer en behoud van het textiel.