Identification of Dyes on Textiles from RI-100 A Seventeenth Century Narragansett Burial Site

Ninety-one woven wool textile specimens from a mid-seventeenth century Narragansett Indian burial site were selected for dye analysis. Transmission spectrophotometry of extracted dye solutions and thin-layer chromatography were the methods of identification for mordant dyes. Non-mordant dyes were reduced in ammonia and sodium hydrosulfite before dilution in butanol for spectrophotometry. Fifty-seven specimens gave positive results in one or both of the tests performed on them. Twenty-eight specimens were positively identified as indigo, twenty-seven as madder. Thirty specimens were undyed and four yeilded inconclusive results. Two fragments suggested the presence of the insect dye kermes, one of which may also have been dyed with a hydroxyflavone yellow dye. These results were examined for their implications regarding test methods, historical context, conservation decisions and the applicability of the test methods to small specimens.


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To the naked eye the fragments ranged in color from red-brown to blue and black. Microscopic examination of the textiles revealed that some textiles had mineralized and some of them were originally dyed in shades of red or brown, blue or possibly purple, green and black. Without laboratory testing of the dyestuff, speculation regarding the original colors of the samples could have been misleading. Even with the identification of the dyestuff, the original color and its source could only be guessed as the color produced could vary with mordants, application time or technique and subsequent change in ground. Nonetheless, dyestuff identification provided information regarding Native American consumption of European textiles in the seventeenth century.
The research had four goals. The first was to identify the dyes or dye types on the Rl-1000 textiles using thin-layer chromatography, transmission spectrophotometry and a specific test for indigotin. Evaluation of these analytical techniques of dye identification for application to miniscule specimens was the second goal. Comparison of the findings to the historical record for cultural context was the third objective. Finally, the dyes found were evaluated in terms of conservation decisions regarding the handling and storage of the remaining Rl-1000 textiles. show that the most common fabrics ordered were "shag" cotton, trading (or trucking) cloth and duffields (Thomas 1985, 182).

BACKGROUND
Textile and costume historians give definitions of fabric types, while dye historians discuss the availability and popularity of dyestuffs in the seventeenth century. Excavation reports provide burial context, and analyses of grave goods suggest a culture's daily existence. Cultural values or religious practices are sometimes indicated by mortuary practices.

INDIAN PREFERENCES
Records show the Indians of New England were discriminating consumers, selecting fabrics of particular weaves and colors. Even in the sixteenth century, preferences were apparent. In 1524 the explorer Giovanni da Verrazano wrote that "They rated blue and red above all other colors." (Wroth,138). Gifts of red coats from the governors of the Massachusetts Bay Colony to Indian leaders were recorded in 1621 and 1638 (Mourt,60;Winthrop,271 ). William Wood wrote in 1635: "If their fancie drive them to trade, they choose rather a good coarse blanket through which they cannot see, interposing it between the sun and them ... " (1977,.

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Previous analysis of the Rl-1000 textiles indicated that the fabrics duffields (twill weave) and trading or trucking cloth (plain weave) were widely acquired by the Narragansetts . The Pynchon trade documents note the yardage of these fabrics, as well as "shag" cotton (a worsted, napped wool fabric), ordered for trade in Massachusetts. Color was frequently specified. Red, blue and white were the most common colors.
Further, trading cloth and duffields were preferred in blue, while "shag" cotton was ordered in red almost seventy percent of the time (Thomas 1979, 304). In 1677 Robert Plot described the manufacture of duffields and trucking cloth in England in the following manner: These duffields ... otherwise called shags and by the Merchants, trucking cloth, they make in pieces about 30 Yards long and one Yard 3/4 broad, and dye them Red or Blue, which are the Colours that best please the Indians of Virginia and New England .... (Montgomery 1984, 228 ... after a sort fit for the Indian trade without any Nape with a white stripe through the selvedge ... but if you see Cause to send any of these they must be all blews ... Next the blews the red sells best and next the Red the purple (Montgomery 1984, 159).
Striped fabrics were among those found at the Burr's Hill site in Warren, RI . Strouds were another fabric traded to the Indians. Several early eighteenth century records indicate the popularity of red and blue ·strouds among Native Americans. Rad strouds were particularly noted for the quality of color achieved by dyeing with cochineal mordanted with tin (Montgomery 1984, 353). The use of tin as a mordant increased in the seventeenth century (Brunello 1973 202).
Trader Robert Hull repeatedly informed his factors concerning low color intensity, writing that only "good sad colors" or black sold in Boston (Baumgarten 1974, 233-4). Roger Williams noted that the Narragansetts specifically preferred "sad" colors, or those colors "without any whitish hairs" (160).

DYES AND DYE TRADE
Although many seventeenth-century Europeans used undyed fabric, numerous textile dyes existed to produce a variety of colors. Mordants, metallic salts applied to the fabrics, were used to enhance the fastness qualities of non-vat dyes and allowed a wider range of colors. Vat dyes did not require mordants and are characterized by their insolubility in water. They require reduction in alkaline sodium hydrosulfite to become soluble and dye fibers. Once on the fibers, vat dyes are returned to their insoluble form by oxidation either in air or with chemical oxidizing agents. The insolubility of vat dyes makes the dyeings fast to wet treatments if applied correctly.
English fabric manufacturers commonly either dyed their goods themselves or sold unfinished goods for coloration elsewhere in England (Kerridge,. In either case, the dyes in use were derived from natural sources, typically plants and insects. They included logwood bark and tannin with iron and vitriol for black; woad and indigo leaves for blues and purples; madder root and the bark of brazilwood trees for reds, oranges, and browns; weld and fustic plants and quercitron bark for yellows, and dried kermes and cochineal insects for crimson and scarlet. Woad or indigo was combined with madder to yield red-purples and with weld or fustic to produce greens. Although other dyestuffs also were available, these were the most common in Europe in the seventeenth century Wilson 1979, 88).
As a source of blue, indigo, a vat dye, was imported to Europe in large quantities by the early seventeenth century with the establishment of the East India companies (Geijer 1979, 208). Prior to this time the English used woad, a plant which secreted the same dyestuff as indigo, indigotin, but in lower concentrations (Brunello 1973, 145-190); thus the two are chemically indistinguishable. Blues produced with comparable quantities of woad were much lighter than those dyed with indigo. Indigo imports threatened local woad producing industries in Europe, and both the use of indigo and the increasing sales of imported indigo-dyed textiles were outlawed for a period of time in England during the Elizabethan period as well as in France and the Netherlands (Birrell 1973, 385;Adrosko 1968, 45-6;Sandberg 1989, 27-8).
Brunelle stated that woad and indigo were in competition soon after the discovery of the New World, but he suggests that indigo use did not completely overtake woad until the middle of the eighteenth century (1973, 196; 227).
Logwood, when used with a complex mordant containing iron, copper and aluminum salts, was the first single source of black. Additionally, with a different mordant logwood produced a fugitive dark purple. Derived from the bark of a Mexican tree, it was imported to Europe by the sixteenth century.
Although its use was banned in England in 1581 due to its variable fastness, logwood was smuggled into the country for dyeing cloth. Prior to the discovery of logwood, blacks were achieved through numerous overdyeings of various substances such as nut galls, iron, tannin, vitriol, madder and woad (Brunello 1973, 190;197;243).
Madder was the most common source of reds, oranges and browns.
Madder was quite inexpensive and, if properly mordanted, reasonably fast to water and light. Its only drawback was that the color range was limited to dull orange reds (Wilson 1979, 91 ). Between the late fifteenth and the eighteenth centuries the Dutch excelled at madder cultivation and dyeing. They were the primary source for both raw madder and madder-dyed wool (Leggett 1944, 11-13).
Brazilwood was used in Italy as early as the Middle Ages to obtain bright reds. It was imported to Europe from as early as the fourteenth century but produced dyeings that were not fast (Brunello 1973, 130).
Until sometime during the seventeenth century European dyers used kermes, an insect dye exported from the Mediterranean, to achieve pinks and scarlets. Kermes was expensive because the source was the actual insect which had to be plucked at a specific stage of development from the leaves of the plant on which it was feeding. Recent literature has suggested that kermes dyes were made from a variety of kermes insects, although Kermococcus vermilius has been thought to be the source of "true" kermes dye (Cardon 1990, 191-2;Brunello 1973, 199-200).
The alternative to kermes was cochineal, a similar insect found in Central and South America. During the seventeenth century, cochineal superseded kermes, although the date when kermes was no longer used has been debated ). Kerridge says that as late as 1622 madder, kermes and cochineal were all in use in Norwich, England (1985, 168). Spain monopolized the importation of cochineal (which was quite large by the mid-sixteenth century) and traded it to the Flemish and the French. Cochineal insects produced more dyestuff than kermes, thus fewer insects were required, yet it was less popular in England and Italy than in France and the Netherlands (Brunello 1973, 62;199-200). Like kermes, cochineal was quite expensive but when properly mordanted, produced a faster, heavier dyeing in bluer shades of red than madder.

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Several plants producing yellow dyestuffs grew in England. The most common were fustic and weld (Adrosko 1968, 31-2;37-9). The colors they produced tended to be light in shade and fugitive to light and water. When overdyed on woad or indigo they produced green, a color for which no single natural source existed (Brunello 1973, 138-9). Another source of yellow, quercitron, derived from the bark of the American black oak, was native to the northern New World and exported to England as early as the sixteenth century (Adrosko 1968, 32-34 Weeden, 1910, 115). Identification of dyes alone does not indicate the location of the dyeing process.

PREVIOUS ANALYSIS OF DYES ON ARCHAEOLOGICAL TEXTILES
Although interest in the identification of historic dyes has increased among scholars, only a few have addressed the identification of dyes on archaeological textiles. Still fewer have analyzed dyes on North American archaeological textiles. Additionally, synthesis of dye identification with historical information such as chronology, material culture, costume and textile history or religious practices is comparatively rare. One of these areas might be addressed, but wider conclusions seldom are drawn.
Generally, the approach to archaeological textiles has been to use the same test methods as those used on unburied samples. Usually the dye is extracted from the fibers by heating in a solvent mixture or reducing agent solution. The extract is then examined using one or more tests. The most common methods are infrared (IR) or ultraviolet-visible (UV-VIS) spectrophotometry, and high performance liquid (HPLC) or thin-layer chromatography (TLC). Although problems have been noted with these techniques, some adjustments have been made to accommodate archaeological samples. These include abandoning one technique for another, and modifying tests to increase sensitivity for small amounts of extracted dye and make allowance for soiled samples.
An early effort to identify dyes on archaeological fabrics used infrared spectrophotometry.  confirmed the presence of alizarin (one of the main components of madder), cochineal (an insect dye), indigo and saffron on wool samples found in the Judean desert and dating to 135 AD. Textiles excavated from desert sites have generally been in better condition and the colors have been brighter than those found in temperate climates. Dye identification on these textiles might have been easier than the identification of dyes on archaeological textiles from wet sites. , , Geiss-Mooney and  and  examined textiles from Pre-Columbian sites in Peru. Despite approaching the subject differently and using various methods, all of these researchers agree on the presence of indigo, cochineal and relbunium (a relative of madder). Hatchett, using a modified extraction method and UV-VIS spectrophotometry, focused on certain red-dyed fibers from one mummy found in Paracas, dating 400BC to 400AD. She found relbunium and a single example of cochineal. Geiss-Mooney and Needles used a succession of solvents and UV-VIS to examine late Intermediate textiles and found cochineal, indigo and undyed fibers.  utilized standard extraction methods and UV-VIS spectrophotometry to test selected fibers from several time periods, primarily the early Paracas period. With a log density scale to minimize concentration effects, he identified shellfish purple, cochineal, relbunium, indigo, a mix of indigo and cochineal and an undetermined yellow dye.
Interestingly, with HPLC Wouters and Rosario-Chirinos found most of the above noted dyes on textiles dating between 300BC and 1532AD and were able to identify Saltzman's unknown yellow as a mixture of several different yellows. Among them were quercitron, luteolin (the dyestuff in the European plant weld) and tannin. Additionally, yellows were found in conjunction with both relbunium and indigo, suggesting that oranges and greens were among the colors of Pre-Columbian textiles.
Although these researchers identified the same dyestuffs to greater or lesser extents, apparently none needed to deal with the limitations of sample size or contamination, and few put their results into a historical context.
Wouters and Rosario-Chirinos began to organize their results chronologically l 3 and found that some dyestuffs were found only on textiles from some limited time periods.
In Europe, many reports of archaeological textile analyses have been published especially since 1969. The primary test methods used are TLC and UV-VIS spectrophotometry.
In an article on the use of thin-layer chromatography and spot tests, Schweppe noted the successful identification of indigo on brown wool fibers from a fifth century BC Celtic grave in Luxembourg (1976, 34). Although his sample weighed less than ten milligrams, he was able to extract indigotin in acetic acid and confirm this result by re-forming an indigotin vat to dye a cotton yarn blue. Unfortunately, the method reported lacks the detail necessary to follow his procedure. Elsewhere (1988), Schweppe described the identification of indigotin through reduction in ammonia and sodium hydrosulfite.

Taylor and Walton have written about their work with Roman (1983),
Anglo-Scandinavian (Taylor 1983), Viking-Scandinavian ) and Medieval European  textiles. They have made comparisons of dye types as welL Lichen purples were the subject of several more articles by Walton and Taylor, the result of discovery at several sites including Roman Vindolanda as well as Viking York. They concluded that lichen purples were in use in Dark Age Europe, despite the research of some historians to the contrary (Taylor & Walton 1983).  reported the progress of study on Viking Danish textiles dating as early as the pre-Roman Iron Age. She found the dyes comparable to those found in Viking York. Madder and indigotin were found in both places as were combinations of the two. In addition, in Denmark, an unidentifiable yellow dye was found. In a later survey of Viking-age dyes,  l 4 noted that the same yellow was found in Dublin, Ireland, along with madder, lichen purple and indigo. She broke down dye identification results along geographic lines finding variations in the proportions of each of the dyes.
In discussing her results, Walton noted that only about half of the samples tested gave positive results and that those which did not test positive might have been undyed or have been dyed with a dye that did not survive burial. Finally, Walton raised the issue of a representative sample. Given the fragile nature of textiles, Walton questioned if the fabrics found at a site were statistically significant samples of the textiles possessed and used by the inhabitants.  raised the same issue in her discussion of the identification of dyes on Egyptian textiles from as early as 1400 BC through 1500 AD. From the identification of dyes and comparison of the number of dyed and undyed samples, Eastwood discussed differences in the range of colors used, as well as the fibers on which they were dyed.
The practical difficulty in identifying yellow dyes has been noted in several articles ( e.g. Taylor 1990A;Walton and Taylor 1991 ).
Solution spectrophotometry cannot effectively distinguish yellow dyes on archaeological textiles because, when stained with residual soils, the extract is contaminated, masking absorption at the wavelengths that yellow dyes absorb. Nevertheless, Schweppe (1986) and Walton and Taylor (1991) reported successful identification of yellow dyes with thin-layer chromatography. However, Schweppe was not testing archaeological dyes and despite noting the use of TLC for archaeological textiles, Walton and Taylor did not report specific results.
Pritchard had Walton analyze dyes on medieval Saxon fabrics (1983) as well as sixteenth and seventeenth century textiles (1991) excavated in London. On the Saxon textiles three dyes were found: madder, woad and I 5 orchil (a lichen purple dye). The later textiles produced madder, cochineal, tannin and possibly turmeric and lichen purples. In comparison to fabric quality the more expensive dyes, such as cochineal, were used on the more expensive silk fabrics. Naturally pigmented fibers were not dyed.
Additionally, Pritchard cited seventeenth century fashion trends in discussing the finding of cochineal on knitted wool stockings.  are among the few researchers working on textile dyes in North America. They noted problems working with archaeological textiles. In examining Hessian soldier uniform fragments from a Revolutionary War gravesite near Charlottesville, Virginia, they found TLC ineffective in identifying dyes on samples caked with clay even after cleaning.
Success was achieved with infrared spectrophotometry. This would seem to underscore the need for a test method which compensates for soils. Taylor Commission, the fragments were characterized according to grave location, color under fluorescent light, fiber content, yarn diameter, yarn twist, weave structure, thread count and finish (Welters 1985, 4-5). Cross-referencing of these characteristics identified thirty two different fabrics along with a number of single yarn samples (Welters MS).
For this research, yarn specimens were removed from fragments large enough that characteristics such as weave structure would not be dismantled.
In addition, specimens were taken from masses of fibers that had no discernible yarn orientation. No specimens were taken for dye analysis when only fibers or a few yarns remained on matting or other materials, The specimens were categorized by fiber content, quantity of sample and hue.
Two additional specimens were chosen because of recommendations from previous research. A red wool fragment had both mineralized and apparently unmineralized fibers of the same hue. A blue-green fragment exhibited the same phemonenon . The source of the color was an unanswered question. Several fragments of a single textile exhibited different colors or appeared to include more than one color yarn. Specimens of these textiles were selected for analysis to determine whether the same dye produced different colors with age and burial or if several dyes were present in the same fabric. In all, ninety-one wool specimens were selected for testing.
Fifty-six specimens representing a variety of colors and graves were analyzed using the test methods discussed in the following sections. After experience was gained in the testing procedures, the remaining thirty-five samples were analyzed using either the reduction test for indigotin or spectrophotometry for mordant dyes. The test method for these remaining specimens was selected based on their color under the microscope; that is, blue specimens were tested by reduction in ammonia and sodium hydrosulfite and reds by spectrophotometry. l 7

COLOR CLASSIFICATION
The Rl-1000 fabrics had been categorized according to Munsell Soil Color charts in previous visual analysis under fluorescent light .
In this research color analysis continued with examination under both the stereo microscope and the polarizing light microscope with fibers mounted in deionized water. Specimens were described as blue, green, red, brown or yellow. Based on these color descriptions indigo, woad, madder, kermes, cochineal, weld and old fustic were considered the dyestuffs most likely to be found on the Rl-1000 textiles (Brunello 1973;Leggett 1944).

CHOICE OF ANALYTICAL TECHNIQUES
A wide range of literature was reviewed to select analytical methods.
Most notable are Taylor's (1983;1990A & B; and  use and refinements of ultra-violet and visible solution spectrophotometry, plus Hofenk-de Graaff's and Roelof's (1969; and Schweppe's (1976; use of thin-layer chromatography and spot and lake tests. Wouters (1991) and  have both used high performance liquid chromatography, and  used infrared spectrophotometry.
Based on color, the specimens were categorized as likely to be colored with a vat dye (blues) or a mordant dye (yellows, reds, browns). Two sets of tests were used on each of the first fifty-six specimens, one test on the remaining specimens. The two test methods were chosen to cross reference results. Procedures were selected for their simplicity, cost, speed and suitability for the small size of the samples, generally three milligrams or less.
For mordant dyes solution spectrophotometry and thin-layer chromatography were chosen. Because blues could only have been achieved with vat dyes, blue and green specimens must have been colored with vat or vat-mordant dye combinations. Therefore blue and green specimens were reduced to solubilize the dye and re-oxidized to identify indigotin. To confirm the indigotin result, the extracted dye was diluted with butanol for spectrophotometry.
Other methods, such as spot or lake tests, were not appropriate as they require much larger samples. Additionally, infrared spectrophotometry and HPLC require expensive equipment not available at the University of Rhode Island's textile laboratory.

IDENTIFICATION OF MORDANT DYES
Analysis of mordant dyes involved two major steps: extraction of the dye and identification by spectrophotometry and thin-layer chromatography, Extraction of known and unknown mordant dyes was based on procedures outlined by Walton and Taylor (1991 ). Known dyed wool samples to be used for comparison were obtained by the researcher from the Conservation Analytical Laboratory of the Smithsonian Institution during a course in dye identification with Dr. Helmut Schweppe in 1990.
A sample was placed in a test tube with one to two milliliters ethanol:10% sulfuric acid (2:1), heated at about 90 degrees Celsius for approximately one hour before cooling to room temperature. The sample was removed, and the extract was shaken with one to two milliliters diethyl ether. After approximately a minute the ether separated the extract into upper and lower layers, with extracted dye in the upper, ether phase. The ether-dye layer was removed with a dropping pipet and evaporated to dryness in a watch glass at room temperature. At this point a few drops of methanol were used to dilute the concentrated dye for TLC.

THIN-LAYER CHROMATOGRAPHY
Thin-layer chromatography was carried out on Baker-flex 6F 5X20 centimeter polyamide-covered plastic plates, cut to approximately five by ten centimeters in length. Prior to dye extraction, separation chambers were prepared with an eluent chosen for the type dye expected to be present. Pretesting resulted in the following choice of eluents: toluene and acetic acid (9:1) for vegetable reds; butanone-methanol-formic acid (65:35:5) for insect reds (kermes and cochineal); chloroform-methanol-butanone-formic acid (6:2:1 :1) for hydroxyflavone yellows (Schweppe 1988, 12). About ten milliliters of the selected eluent was poured in to the 12x4x9 inch separation chamber. The chamber was covered and left undisturbed for one to two hours, allowing the eluent vapor to saturate the chamber.
Using micropipettes, a maximum of one known and three unknown dye specimens dissolved in methanol were spotted on the plates in a line close to one centimeter apart and approximately one centimeter from the bottom and each side. For insect reds one unknown was accompanied by both a kermes and a cochineal specimen.
After chromatograms air dried they were placed in the separation chamber. The chamber was covered, and the chromatogram was allowed to run until the eluent had travelled up the plate surface approximately eight centimeters. Immediately on removal the distance travelled by the eluent was marked with a pencil, and the chromatogram air dried before soaking in 0.5% methanolic uranyl acetate for up to a minute. After unsuccessfully trying ultraviolet fluorescence and potassium acetate, uranyl acetate was found to be the most effective in making faint chromatograms more visible. Finally the chromatogram was examined. Evidence of dyestuffs was noted and compared to knowns.

SPECTROPHOTOMETRY
Prior to testing, several weeks were spent perfecting technique and creating a library of reference spectra from known dyed wool samples. Large and small specimens of each dye extracted from these fibers produced spectra of high and low concentrations of each dye. This range of concentrations showed the variation of spectra that could be expected. The low concentration was chosen to approximate the size of the unknown samples from 1.0 to 3.0 milligrams. Additionally, following Taylor, after the first spectrum, each dye solution was treated with magnesium acetate tetrahydrate and a second spectrum was taken. Magnesium acetate has been shown to cause characteristic intensification of light absorption by certain dyestuffs (Taylor 1983, 155).
Following TLC, the remaining concentrated unknown dye was diluted with approximately four milliliters of methanol, poured into a rectangular glass container called a cuvette and placed into the 2020 Macbeth spectrophotometer. A transmission spectrum was measured and plotted by the spectrophotometer using Macbeth Optimatch software. Additionally, one gram of magnesium acetate was added to the four milliliters of dye solution for a second spectrum. The spectra of the unknowns were compared to those in the reference library, similarly prepared and treated with magnesium acetate, for identification. Results from TLC and spectrophotometry were compared to identification of dyes.

MODIFICATIONS TO THE SPECTROPHOTOMETER
Pre-testing showed that although the extraction method was effective, and the addition of magnesium acetate intensified the dyes' absorption of light, the Macbeth 2020 spectrophotometer (designed as a reflectance instrument) used a cuvette measuring four by three by one centimeters, requiring 10 milliliters of solution when used for transmission measurements.
This presented a problem because known specimens the size of the Rl-1000 fragments produced ten milliliter extracts that were too low in concentration to produce usable spectra. Modification was necessary.

IDENTIFICATION OF NON-MORDANT DYES
For specimens which appeared blue or green the researcher assumed that the unknown dyestuff was indigotin, either alone or in combination with a mordant dye. Schweppe's (1988, 17) procedure for the reduction of vat dyes was followed .. Specimens in test tubes were boiled in approximately two milliliters of concentrated ammonia with about two milligrams sodium hydrosulfite. Specimens with dyes containing indigotin produced a yellow solution of reduced or leuco-indigotin, called a vat. The addition of butanol yielded a blue upper phase within a minute when indigotin (the primary dyestuff in indigo and woad) was present. For confirmation, spectra were measured. The butanol layer was removed with a dropping pipet, put into a cuvette and diluted with butanol to a quantity of four milliliters for spectrophotometry. Interestingly, lichen dyes and shellfish purple dyes also respond to the vat dye test although they are not actually vat dyes.
After spectrophotometry, fiber specimens were removed from the remaining ammonia, rinsed in water and examined under the stereo microscope for retention of any additional color. Any remaining red or yellow color would have suggested an over-dyeing. None of the specimens exhibited additional color. Had other colors been retained, the mordant dye would have been extracted and tested following the procedure for mordant dye analysis outlined above. Schweppe (1988) has found that the vat dye test does not destroy mordant dyes, allowing the vat dye test to be performed before testing for mordant dyes.

RESULTS
Ninety-one specimens representing fourteen different graves were analyzed for evidence of dye. Of the ninety-one, fifty-seven gave positive results in one or both of the tests performed on them (see table. 2) Twenty-eight specimens total tested positive for indigotin ( fig.2). Of 24 these, two specimens tested positive for indigotin in the vat test, however with the dilution of the butanol to four milliliters, these two extracts were too weak to yield conclusive spectroscopic results. Additionally, after an inconclusive vat test, the spectrum of a third specimen indicated indigotin.

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9J . Twenty-seven specimens tested positive for madder. Of these, thirteen specimens indicated madder by both TLC and spectrophotometry with and without magnesium acetate. The TLC of a known madder and the unknown sample seen in figure 3 i•s an example. Figure 4 demonstrates the spectra of known madder with and without magnesium acetate. Figure 5 is the spectrum of the unknown dye in figure 3; comparison of figures 4 and 5 confirms the identity of madder suggested by the TLC.
Spectrophotometry alone of twelve specimens indicated the presence of madder. Two specimens tested positive for madder in TLC, but the four milliliter spectrophotometry extracts were too dilute to confirm the TLC results.
Kermes was indicated in the TLC of one specimen, but spectrophotometry was inconclusive. In thin-layer chromatography another sample showed both a hydroxyflavone yellow and an insect red, probably kermes. However, spectrophotometry was unable to confirm these results.
No other fragments yielded positive yellow dye results. One sample exhibited neither madder nor insect red results in TLC, but with absorbance maxima at 400 and just over 500 nanometers; its spectrum suggested two dyes ( fig.6).  Incomplete dye penetration of the fabric (due to piece-dyeing or unrefined dyeing methods) is another possible reason for inconclusive results.
Microscopic examination prior to dye analysis revealed several specimens with poor dye penetration both of yarns and fibers. The selvedge ( fig.11 ), while predominantly blue, shows several straw colored areas where dye did not penetrate the yarn. In a longitudinal view of a fiber ( fig.12), dark blue fades to yellow-green and begins to darken again, indicating that dye did not completely penetrate the length of the fiber.
Although many specimens appeared to be different colors under the microscope, frequently the same dyestuffs were present. Most blue specimens, variously described by researchers as blue, blue-black or bluegreen,were, as expected, based on indigotin. Similarly, most specimens described as red, red-brown, orange or dark brown were based on madder.
Several factors may have contributed to color differences. Original mordants, amount of dye or fugitive over-dyes would have affected color. Equally important, soils associated with use and burial with grave goods could affect the color of excavated textiles, underscoring the importance of laboratory dye analysis.

RESULTS IN THE CONTEXT OF EUROPEAN-COLONIAL TRADE
The presence of madder, indigo or woad and probably kermes supports the theory that the woven wool fragments found at Rl-1000 were produced and dyed in Europe (Welters MS,5 were common dyes throughout Europe in the seventeenth century  ). However, it is not possible to determine where the textiles were dyed by the identification of these dyestuffs.  The shift from the use of kermes to cochineal occurred during the seventeenth century. Coupled with the issue of multiple kermes insects, the two kermes results of this research raise some interesting questions. Is the presence of kermes significant ? Due to its declining use at this time, kermes must have been hard to find and it was more expensive than madder. This suggests an intentional selection of a kermes-colored fabric. Although depending on the mordant, an insect dye might have been made to produce a color similar to that produced by madder, the cost of using kermes makes this scenario improbable. Alternatively, a kermes-colored textile may have been the only one available at the time of acquisition or burial.
Textiles were valuable and constituted large proportions of the material wealth of European settlers (Thomas 1985, 146;. In this context, domestic production was desirable. In fact, efforts were made by the Colonial government to encourage both the raising of sheep and fabric production in the home. However, written records demonstrate that domestic production could not meet the demand for woven fabrics (Baity 1949, 233-4).

Merchants such as Roger Williams, the Pynchons and John Hull repeatedly ordered textiles of all sorts from Europe to trade both with Colonists and
Native Americans, stressing that the colors and fabric types should be those that sold well both to groups (Welters et al. in press,.

IMPLICATIONS REGARDING CONTACT BETWEEN COLONISTS AND THE NARRAGANSETTS
The abundance and quality of grave goods from Rl-1000 suggest both that the Narragansetts were wealthy relative to other Native Americans in New England and that the interaction between the Narragansetts and Colonial settlers, or at least traders, was common. The Narragansetts were craftsmen and traders, manufacturing shell beads and wampum, as well as trading furs, although the most active fur trade occurred farther north (Robinson et al. 1985, -110). Further, researchers suggest that Colonists were reliant on Native

American wampum as a currency of exchange between themselves and other
Indians (Thomas 1985, 156). The implication is that the Narragansetts were in a position to be selective in their choice of European goods. Documentary sources, such as the records of Robert Plot and Roger Williams and the descriptions written by Gookin, report the Native Americans preference for red and blue fabrics which is supported by the results of this research.
Several interpretations are not mutually exclusive. The use of traditional mortuary practices to reaffirm cultural identity at a time of instability has been related to Rl-1000 (Robinson et.al. 1985, 122-3). Despite the trend towards traditional burial practices, evidence of European contact is still seen in the textiles found in these graves. Perhaps red and blue textiles were important to the Narragansetts in everyday life and so might have held mortuary significance.
Care must be taken in attributing preferences to the Narragansetts.
Although it is not known if these ninety-one specimens constitute a representative sample of Narragansett European textile consumption, the predominance of two particular dyes on the textiles cannot be ignored.
Excluding the samples from the fill dirt originally excavated from several graves, madder was found in seven graves, indigotin in five and both dyes were present in four. While madder was commonly available and relatively cheap in the seventeenth century. Cochineal, and, to a lesser extent kermes, also were available but expensive (Hofenk-de Graaff 1969, 83). The finding of two kermes specimens at Rl-1000 might reinforce the idea that fabrics colored with madder were preferred. Given that the Narragansetts were selective in trade, a reason for choosing reds and blues must exist. The low cost and ease of availability of madder, and the depth of shade and color fastness of colors produced by indigotin make their presence on the Rl-1000 textiles unsurprising.

IMPLICATIONS FOR CONSERVATION 36
The extensive post-excavation treatment received by the Rl-1000 textiles does not appear to have affected the identification of the dyes, although the proportion of conclusive results might have been higher had they not received consolidation treatment. Post-excavation treatments should be carefully selected so dye is not lost or chemically altered.
Indigo and madder are two of the most fast natural dyes. lndigotin is not water soluble in its oxidized form, nor is it vulnerable to photo-degradation (Bide 1992, 37). Mordanted madder has fair to good fastness to both water and light (Adrosko 1968, 95-6). In terms of the storage or exhibition of the Rl-1000 textiles, the fibers themselv_es are probably more of a concern than the dyes used on them. Fiber degradation is exponential; the more damaged a fiber, the more vulnerable it is to further degradation (Bresee1986, 41-6). The  concentration, potentially yielding quantitative information (Duff & Sinclair 1989, 134).
In this research, quantitative results were not necessary for identification.
Such measurements would have reflected the concentration of the dye extracted from the textile as opposed to the amount of dye originally on the textile. Were quantitative information necessary for this research, one of the factors to be considered is the concentration of the dye in the extraction. If the concentration is low, quantitative information may be inaccurate. To compensate a logarithm of absorbance or density may be plotted Saltzman & Keay 1967).
Dyes can be identified by analyzing the spectrum of either a textile itself or a solution of dye extracted from the textile. Solution spectrophotometry was most applicable to this project because the specimens, although they have been cleaned, were small archaeological specimen which retained dirt (Welters 1985, 2-3). Soils often can be separated from dyes in solution, before testing, preventing excessive distortion of a spectrophotometric curve (Taylor 1990A, 1156. Additionally, transmission spectra provide more fine detail . Taylor (1983) enhanced the sensitivity of his method by adding magnesium acetate to the extraction. Magnesium acetate chelates the dye molecules and increases the dye's absorption of light. In transmission spectra the result is a reduction in the percent of transmitted light, so the curve is intensified.

Methodology
Solution spectrophotometry has been described by several authors for industrial as well as historical research. In all cases, the dye must be extracted from the textile by placing the sample in a solvent and either heating it for a period of time (Taylor 1983;1990 A&B;Saltzman 1967; or allowing the solvent and sample to sit at room temperature for a longer period of time . Variations on these methods include using complex solvents (Geiss-Mooney & Needles 1981) or a progression of solvents (Macrae & Smalldon 1979).
The result of extraction is a colored solution the transmission or absorbance of which is measured by the spectrophotometer. It produces a curve of absorbance maxima characteristic of the dye in a particular solvent.
The absorbance maxima of the unknown are compared to reference curves of known dyes in the same solvent(s).

Limitations
Several problems are associated with solution spectrophotometry of dyes on archaeological textiles. The extraction method may be destructive to the sample, necessitating the use of small amounts of textile. Indeed sometimes only small samples are available. Both circumstances require careful laboratory procedures to extract enough dye to be read by the spectrophotometer. Another limitation is the need for a library of reference samples made from known dyes in a variety of solvents, not always available in the literature. Because dyes produce different curves in different solvents, one curve for each dye may not be sufficient. The production of such reference cuNes is time consuming.
In addition, a problem has been encountered by some in identifying yellow dyes on archaeological textiles with spectrophotometry. Natural yellow dyes are fugitive, thus producing pale extractions in which contaminants can easily distort the cuNe. The solution may be so pale that no cuNe is produced or the resulting cuNe may be uncharacteristic (Taylor 1990A & B).
The largest drawback of spectrophotometry is in interpreting spectra of combinations of dyestuffs (Feeman 1970).  wrote that spectrophotometry can in fact reflect combinations of dyes, if the dyes are soluble in the same solvent. Obviously, if the sample is an unknown, one may not know if more than one dyestuff is present, much less if they are soluble in the same chemical. Clearly, in some cases one would be aware of a mixture: if a sample were green, and only the yellow dyestuff, weld, appeared in the cuNe, one would know to re-test in different solvents until a blue source was reflected. Additionally, the burial environment might alter colors to the point that although they now appear similar in color, they might contain of a variety of dyes. Taylor (e.g. 1983;; 1991) developed a system of examination that helps solve the problem of identifying combinations of dyes. His method begins with extraction in pyridine and water. This process will dissolve vat dyes but will not affect the mordants used with other natural dyes. A spectrum of the pyridine-water extraction is taken. If no dye is extracted, the sample is rinsed and boiled in ten percent sulfuric acid and ethanol after which the solution is shaken with diethyl ether to separate soils from the dyestuff. The ether is evaporated before the dyestuff is dissolved in methanol for a final spectral analysis.

Thin-Layer Chromatography
Many articles describe the technique of thin-layer chromatography (TLC) primarily for industrial purposes (e.g. Bide & Choi 1992;Brown 1969;Feeman 1970;Macrae & Smalldon 1979;Sweeney 1972). Some articles contain a great deal of practical information on technical refinements (e.g., Rettie & Haynes 1964;Anonymous 1969). More recently, TLC has been used for historical dye identification by several researchers, including Schweppe (1976; 1986; 1989), Taylor (1990A;1990B; and Hofenk-de Graaff (1974;1975;. Thin-layer chromatography is a tool used to separate organic compounds. Separation occurs when substances in solution (in this case dyestuffs in methanol) are carried across a substrate (cellulose, silica, aluminum or polyamide) through the capillary rise of an eluent (carrier).
Throughout the rise of the eluent, solutes are adsorbed from the eluent on to the surface of the substrate at different rates (Rettie & Haynes 1964, 632).
Because of its basis in relative rates of adsorption, TLC is useful in identifying mixtures of dyestuffs (Feeman 1970, 84;Rettie & Hc3:ynes 1964, 629). In this capacity it is more useful than spectrophotometry.
The mechanism of thin-layer chromatography is a balance of the relative affinities of the three substrates involved: the adsorbent (substrate), the solute (dye) and the solvent (eluent) (Bide & Choi,133). Affinities are affected by polarity and molecular geometry in that both influence solubility and the attraction of one substance to another. As the eluent travels across the plate, a succession of equilibria are established between the dye, eluent and adsorbent, resulting in movement of the dye -less where the dye is strongly sorbed and/or weakly interacting with the eluent, and vice versa. A particular dye will thus move a characteristic distance. The technique is simple in terms of equipment and method, and the chemicals and equipment are relatively inexpensive. Practice in preparation and reading results is necessary to produce meaningful results.

Methodology
Thin-layer chromatography is a simple procedure. Prior to TLC, the dye must be extracted from the textile, concentrated and redissolved in a second solvent from which the dye under test may be suitably spotted onto the plate.
Then the extract is spotted onto a glass or plastic_plate coated with a substrate (Rettie & Haynes 1964;Brown 1969). Today the plates are usually pre-coated plastic; they are commercially available, and are the most expensive part of TLC equipment.
The dye can be extracted in one of several solvents and usually is concentrated over a steam bath. Methanol is a common diluent. The spotted plate is placed in a separation chamber which has been prepared in advance with the chosen eluent. Approximately ten milliliters of eluent is poured into the 12x4x9 inch closable chamber and allowed to saturate it with vapor for up to two hours. The plate is left in the chamber until the eluent has moved eight to ten centimeters up the plate. This can take between ten minutes and several hours. Once removed from the chamber, the distance travelled by the eluent is marked (Schweppe 1988 Schweppe (1988) devised a procedure of identification applicable to many types of dyes. TLC was one of the primary methods he employed.
Sample preparation begins with boiling the textile in 10% ammonia to cleanse it of contaminants and soils. It is then rinsed in water and methanol, blotted and dried. Next the dye is extracted from the textile first in water, then glacial acetic acid before rinsing in water and boiling in concentrated ammonia and sometimes 10% sulfuric acid. The dyestuff in the most colored of these extracts is concentrated and dissolved in a small amount of methanol for TLC.

Limitations
Thin-layer chromatography shares some of the same limitations as spectrophotometry. A set of reference chromatograms, made under the same conditions as the unknowns, is required. Although TLC has been cited as producing quantitative results (Rettie & Haynes 1964), other researchers question its use in this manner (Feeman 1970). However, for the same reasons that quantitative information may not be required from spectrophotometry, the lack of quantitative results from TLC is not a limitation to this research.
A larger issue is the potential for contaminants in the extract.
Theoretically, this is not a problem as the method is supposed to separate compounds. However,  found that soil adhered to some samples and interfered with TLC. While their method of extraction was not specified, the problem might have been one of laboratory technique that might have been encountered with the Rl-100 samples. Still, Taylor (1990) found extraction and TLC sufficient to separate soil from dye and identify yellow dyes unidentifiable by spectrophotometry. Careful

50"
The molecular and physical structure of wool and its chemical composition directly affect the ability of wool to be dyed. On the molecular level, wool is a protein called keratin, made up of seventeen to eighteen different amino acids held together in a helical formation by hydrogen bonds.
Together with these bonds, two kinds of cross-links between helices provide wool with many of its physical characteristics.
The sulfur atoms in the amino acid cystine form covalent cross-links • called cystine linkages. The cystine links are vulnerable to damage by alkalis.
Ionic links occur between amine and carboxyl groups to form salt bridges.
Together the cystine and salt linkages make wool extremely resilient. At pHs outside the pH4-5 iso-ionic region an excess of positively and negatively charged functional groups are available to react with mordants or dyes (Kadolph et. al 1993, 58-59).
Based on its molecular structure, wool should be a simple fiber to dye.
Due to its physical structure, this is not the case. Each wool fiber has essentially four parts. In the center is a hollow or semi-hollow core called the medulla. Cook says that generally the smaller the medulla the finer the wool and that in modern Merino wool the medulla may be invisible or absent (101-2). Surrounding the medulla is the cortex of the fiber, the area of keratin deposition. It is made up of two regions (called ortho or para) of fibrils which either twist around each other or form a sheath and core. Encasing the cortex is the cuticle, and the epicuticle, the endocuticle and the exocuticle which make up the scales. Scales are responsible for the felting abilities of wool, and together with the epicuticle membrane repel moisture (Cook 1984, 98-102).

1
For dyeing to occur, the cuticle must be penetrated, and dye sites must be available. Heat and moisture will loosen the cuticle to allow the dyes to penetrate, thus most wool dyeing involves boiling in water. The links are pH dependent. At pHs below-4-5, dye penetration and exhaustion are increased by the provision of an excess of positively charged sites. Thus acids often are added to wool-dyeing solutions.

Mordants
Prior to Perkin's discovery of mauvine in 1856, all dyes were derived from natural mineral, animal or vegetable sources. Applied alone most of these dyes were not very fast to light and water. Thus mordants were applied to aid fastness properties. The first use of mordants has not yet been documented, however Middle Kingdom Egyptians (2000-1500 B.C.) are known to have used them (Adrosko 1968,4).
Mordants for wool are metal ions, commonly aluminum, chromium, iron, tin, or copper which function in several ways to yield generally fast dyeing.
The mordant is applied to the wool fibers in the form of metallic salts dissolved in a heated bath. During the dyeing the metal cations react with the wool (Knecht & Fothergill 1924, 189). Later, in a warm acidic dyebath, the dye molecule reacts with the mordanting cation and is precipitated on to the fiber in the form of insoluble lakes (Gohl & Vilensky 1990, 82;148). The resulting metal-dye complexes are chemically more stable due to a sharing of electrons (Aspland 1993, 56) and have increased dye-fiber interaction.
Greater interaction makes acid dyes more resistant to alkaline substances such as laundry detergents (Gohl & Vilensky 1990, 83). Additionally, several of the mordanting metals react with more than one dye molecule producing dye-metal-dye complexes too large to exit the polymeric structure (Smith & Black 1982, 342).

53
The political situation between England and America was tense in the seventeenth century. Elizabeth I died in 1603 and was succeeded by James I.
His son, Charles I, ruled until his death in 1648. Both James I and Charles I were lavish spenders and believers in the absolute power of the monarchy.
Despite England's rising economic fortunes, parliament distrusted royal reports of fiscal need, setting the stage for conflict (Palmer & Colton 1961, 144ft (Stratton 1986, 19). Many were so poor that they could not afford the passage on the Mayflower and consequently were mortgaged to London merchants for seven years after their arrival (Warwick et al. 1965, 95

Fabric Production and Trade
After the arrival in the Colonies, the hardships of survival left little time for Colonists to rear sheep, and produce cloth (Leggett 1947, 234). Thus early settlers were largely dependant on Europe, specifically England and The Netherlands, for goods they could not produce themselves Walton 1925). To the British, the colonies_ represented a captive market, and they dumped out-of-fashion goods on the colonists. Additionally, while not dependent on American trade, the British monopolized American trade, imposing tariffs and trade regulations for their own benefit (Baumgarten 1974, 225). Ironically, as early as 1640 the British trade monopoly stimulated some New England sheep rearing and wool fabric production (Leggett 1947, 237 Although later than the Rl-1000 burials, records show that by 1683, not only were most households engaged in cloth production, they also traded for" ... linsey-woolseys and other coarse cloths from Massachusetts" (Weeden, 1910, 115).
Nevertheless, although Colonial Americans produced woven textiles, merchants' records from the time show that the quantities of domestically produced textiles did not satisfy the need (Baumgarten 1974, 220;Welters et al. in press, 1-3). Indeed, Colonists purchased European textiles in large quantities for clothing, home use and probably trade with Native Americans.
The letters of the Merchant John Hull, although not differentiating between Native American and Colonial preference, repeatedly request a wide variety of fabric. Other merchants ordered textiles specifically for their Indian patrons.
No evidence indicates that the Narragansetts wove fabrics from animal fibers. Instead, they plaited and twined grasses and rushes into mats and cordage. Because of depletion of the fur-bearing animals in the region and exposure to European traders, they began to appreciate the wearing qualities of woven textiles. Eventually, they acquired woven wool textiles from traders such as Roger Williams who procured them from English or Dutch merchants (Turnbaugh, 1993, 133).

56
During the summer of 1982 and 1983 the burials of fifty-six individual Narragansett Indians were excavated in Rhode Island. The site, called Rl-1000, located in North Kingstown, is one of only four known Native American cemeteries of the historic period in southern New England. Both skeletal remains and grave goods were unearthed from the site, and when analyzed, dated the site to 1650-1670 (Turnbaugh, 1984). Found in the graves were goods such as buttons, pipes, brass kettles, spoons and glass beads as well as seventy-six fragments of nine different types of European woven wool textiles and cotton fabrics (Welters MS, 6-10).
Other Native American burial sites have yielded woven wool fabrics as well as some luxury textiles of European manufacture . Until recently the woven wool fabrics in Native American cemeteries have been been overlooked (Welters et al. in press). Upon excavation, the Rl-1000 textiles were cleaned, consolidated, mounted and stored at the Rhode Island Historic Preservation Commission in Providence.
Subsequently MS) characterized the textiles according to yarn size, yarn twist, fabric weave, thread count and finish. The specimens were assigned color notations according to Munsell Color Charts. Coho (1993) examined those textiles which had mineralized, including some descriptions of color. However, the presence of dyes were not confirmed.
Preliminary examination of the Rl-1000 textiles showed mainly heavy, coarse wool fabrics. Most appeared stained by grave conditions, but shades of red, blue and brown were evident in others. Some specimens which appeared blue showed yellow under the microscope, suggesting that green fabrics might also have been acquired. The natural color of the wool might have been yellow enough to produce greens when dyed with indigotin.