Chemical Analysis on Textiles from the Viking Age

Through the use of modern chemical analysis it can be demonstrated that certain plants, chemical coloring agents, and classes of colorants were known and used on textiles from the Viking Age.

Based on chemical analyses of actual wool textiles, the following plants were more or less certainly used to dye wool textiles of the Viking Age.

• Galium boreale (northern bedstraw)
• Isatis tinctoria L. (woad)
• Juglans regia (English walnut)
• Rubia tinctorium L. (madder)
• Xanthoria parietina (common yellow wall-lichen, also called shore lichen)
• at least one lichen that yields purples, possibly from Ochrolechia tartarea

Based on chemical analyses of actual imported silk textiles, the following dyestuffs were more or less certainly used to dye imported silk textiles available in the Viking Age.

• Kermes vermilio (a red Old World bug dye)
• Reseda luteola (weld)
• Rubia tinctorium L. (madder)
• indigotin from woad or indigo
• a lichen purple, possibly from Rocella tinctoris

The following additional plants were most likely used to dye textiles of the Viking Age. Either they sport appropriate chemical proportions of the colorants listed below, or they have been found in Viking Age archaeological contexts suggesting use as dyestuffs.

• Calluna vulgaris L. (heather)
• Diphasium complanatum (also called Lycopodium complanatum, a type of clubmoss probably used as a mordant due to its aluminum content)
• Genista tinctoria L. (broom)
• Reseda luteola L. (weld)

The following unidentified colorants were definitely used to dye textiles of the Viking Age.

• "Yellow X" (see below)

And for the chemists among you, the following chemical colorants were definitely used to dye textiles of the Viking Age.

• Alizarin
• Flavone (on silk)
• Indigotin
• Luteolin
• Pseudopurpurin
• Purpurin

The following mordants are fairly certain to have been used to dye textiles of the Viking Age.

• alum
• copper (from bronze dyepots)
• iron
• tannin (possibly from elm bark, Alnus glutinosa)

Colors on Wool

Wool, the chief textile fiber of the Viking Age, was available in white as well as many different natural shades of browns and greys. Such shades could be and often were spun and woven without ever being dyed. Wool dyes very easily, though, and many finds of wool from the Viking Age were dyed in once-bright colors. Sometimes a dyer might use a naturally pigmented wool rather than a white one.

A report on the analysis of 220 samples of Viking Age textiles mentions 90 samples which yielded evidence of dyes. The samples come from Dublin, Jorvík, and 19 sites in Norway and Denmark; the dyes mentioned are red from madder or bedstraw; a purple derived from lichens; our mysterious yellow X [from an unidentified plant]; and a colorant identified as indigotin, almost certainly derived from woad. The insect dye kermes has also been found, and luteolin, presumably from weld, but only on imported silks. (Walton 1988b, 17)

Yellow X is still unknown. Chemical testing has eliminated 25 possible dyestuffs, including weld, broom, buckthorn, heather, chamomile, and saffron (see Walton 1988a for a complete list of dyestuffs tested).

Blended colors are also represented. Indigotin was used in conjunction with other dyes to produce several purples (with madder) and a green (with the unidentified yellow). Madder and lichen used in conjunction yielded a red-violet result (Walton 1988, 18, figure 9). Some evidence of brown from walnut shells has also been found, as well as one or two pieces that were intentionally dyed very dark brownish-black with walnut shells and iron (Hägg 1984, 289).

The chemical evidence of textiles from several different sites seems to point to a preponderance of particular colors appearing in particular areas: reds in the Danelaw, purples in Ireland, and blues and greens in Scandinavia proper (Walton 1988, 18). This seeming preference could of course be explained by any number of variables--availability of dyestuffs, the differing site climates, or the sheer vagaries of archaeological discovery. However, although it is carefully hedged, there is a hypothesis in the scientific world that this might possibly reflect regional color preferences rather than archaeochemical factors. It is pleasant to think that this sort of "Viking heraldry" might have been practiced.

Colors on Linens

Linen does not take most historic dyes readily, even when a mordant is used. Accordingly, linen was often bleached or left its natural color (grey if dew-retted, straw if water-retted). Substantive dyes such as woad, however, are fairly successful; accordingly, blue linen may have been more common than we know. There are a few examples of woad- and madder-dyed linens from Birka.

Colors on Silks

Imported silks may have gotten their colors from plants or other materials not available in northwestern Europe, such as indigo or Tyrian ("royal") purple. No further consideration is given to this issue in this article.

Sources      

Taylor, G.W. 1983. "Detection and Identification of Dyes on Anglo-Scandinavian Textiles." Studies in Conservation 28, pp. 153-160.

Technical. Discussion is confined to finds of blue and red dyes due to limitations   

of the technology. Plenty of discussion about red dyes.

Taylor, G.W. 1990. "On the nature of dyeings with madder and related dyestuffs." Dyes in History and Archaeology 9, pp. 23-26.

Focuses on the problem of identifying sources of the colorant pseudopurpurin.  

Recounts an interesting experiment: several red dyestuffs are used at different  

temperatures and their thin-layer chromatography results compared. Also

summarizes the results of an earlier madder experiment by Su Grierson.

Tomlinson, Philippa. 1985. "Use of Vegetative Remains in the Identification of Dyeplants from Waterlogged 9th-10th century AD Deposits at York." Journal of Archaeological Science 12, pp. 269-283.

Heavily botanical approach, focusing on the identification process for each set of

plant specimens.

Tomlinson, Philippa, and Allan Hall. 1984. "Progress in Palaeobotanical Studies of Dye Plants 1983/4." Dyes on Historical and Archaeological Textiles 3, pp. 28-29.

Suggests that remains of heather (Calluna vulgaris) found at Anglo-Scandinavian  

York served as a dyestuff.

Walton, Penelope. 1988a. "Dyes and Wools in Iron Age Textiles from Norway and Denmark." Journal of Danish Archaeology 7, pp. 144-158.

A report of a 1985 project: laboratory analysis of over 50 textile samples for

fleece type and dyestuff content. Includes several samples from the Viking Age,

many of them from lesser-known sites. Text includes many graphs and a complete

catalogue of findings in table format.

Walton, Penelope. 1988b. "Dyes of the Viking Age: A Summary of Recent Work." Dyes in History and Archaeology 7, pp. 14-19.

Although kind of technical, the best few-page summary out there. Contains

information on spectrochemical analysis as well as botanical information for

various Viking Age dyes.

Walton, Penelope. 1989. Textiles, Cordage and Fiber from 16-22 Coppergate. The Archaeology of York, Vol. 17: The Small Finds, Fascicule 5. Dorchester: The Council for British Archaeology and The Dorset Press.

Careful, detailed archaeological analysis of the textiles found from the late ninth-

through early eleventh-century period of the Anglo-Scandinavian site of Jorvik.

Helpful discussion on the colors, especially with respect to lichen purple.

Walton, Penelope. 1991. "Dyes and wools in textiles from Mammen (Bjerringhøj), Denmark." Mammen: Grav, kunst og samfund i vikingetid, ed. Mette Iversen, Ulf Näsman, and Jens Vellev, pp. 139-43. Viborg, Denmark: Viborg Stiftsmuseums raekke bind 1. Jysk Arkaeologisk Selskabs Skrifter 28.

A technical report on results of several tested textile samples from Mammen;

includes fleece types, fiber sizes, and some good in-depth information on red

plant dyes.