1 INTRODUCTION

Color has always been an important element in the cultures of peoples all over the world. It was used not only to embellish an object or an individual but to indicate importance and hierarchical status. Some dyes or dyed textiles were even used to pay taxes (Donkin 1977; Born 1938; Baizerman 1985). The painstaking activities of searching for the natural sources of dyestuffs and selecting, extracting, and applying them form a sound basis for their high commercial importance.

In present-day Peru, the technology used by the ancient Peruvians for the production of polychrome textiles has almost completely disappeared. A recent literature and field survey of dye plants traditionally used in Peru beginning in pre-Hispanic times, led to the taxonomic determination of 56 plant species (Antu�ez de Mayolo 1989). In another study, descriptions are given of dyeing procedures utilizing contemporary substrates, mordants, and dyes together with small samples of wool dyed by the procedures described (Zumb�hl 1979).

In previous analytical dye studies various methods were used: comparisons of hues on yarns with the naked eye (Fester 1940); spectrophotometric analyses in the visible region (Fester 1940; Fester and Lexow 1943b; Saltzman 1978; Geiss-Mooney and Needles 1981); paper chromatography techniques (Gibaja Oviedo and Salazare de Cavero 1977); thin-layer chromatography (Schweppe 1986); and infrared spectroscopy (Martoglio et al. 1990). None of these methods involves quantitation of dye components or their spectral characterization. This type of data, however, represents an analytical refinement that might be expected to unravel the dye traditions for which there is sparse evidence from pre-Columbian Peru, e.g., regarding the existence of abundant sources for the production of yellow dyes (Antunez de Mayolo 1989; Martoglio et al. 1990).

The study described in this paper uses high-performance liquid chromatography (HPLC) in combination with diode-array detection in the ultraviolet and visible region (UV-VIS), allowing separation, relative quantitation, and spectral characterization of all dye components detected (Wouters 1985; Wouters and Verhecken 1989a). The knowledge and experience gathered in researching and analyzing Old World dyes (Wouters 1985; Wouters and Verhecken 1989a; Brunello 1973; Hofenk-De Graaff 1969) aided in the recognition of many components in the reference materials from Zumb�hl's publication (1979) (which contains dyed samples) and in historical Peruvian samples. Sometimes, however, it is not possible to characterize chemically all components that, according to their spectra, would contribute to the formation of color in a given dye. Even in such cases, the analytical patterns could be reasonably well interpreted by allocating them in representative and suggestive groups. This means of interpretation was especially possible in the case of the yellow dyes.

Forty-two fabrics were selected from the collections of the Royal Museum of Art and History (Brussels, Belgium) and the Museo Nacional de Arqueolog�a y Antropolog�a (Lima, Peru). The fabrics belong to different pre-Columbian cultures and to the Inca period, covering the era from 300 B.C. to 1532 A.D. The textile pieces were attributed to given cultural periods before any dye analysis was carried out, either by S. Purin of the Royal Museum of Art and History or by the staff of the textile department at the Museo Nacional de Arqueolog�a y Antropolog�a (see table 1).

TABLE 1 HISTORY AND GEOGRAPHY OF PRE-COLUMBIAN CULTURES