Characterizing the Dyes of Pre-Columbian Andean Textiles: Comparison of Ambient Ionization Mass Spectrometry and HPLC-DAD

Jennifer Campos Ayala,Renée Stein,Kathryn Jakes,Brenan Wilson,Ruth Ann Armitage,Kay Antúnez De Mayolo,Samantha Mahan

doi:10.3390/heritage4030091

Abstract

The complex and colorful textiles of ancient Peru have long been a focus of technical study, particularly to characterize the sources of the wide variety of dyes utilized by these Andean artisans. This manuscript describes the characterization of the dyes of both primary (red, blue, and yellow) and secondary (purple, orange, and green) colors sampled from textiles spanning five major civilizations: the Paracas Necropolis, the Nazca, the Wari, the Chancay, and the Lambayeque, all from Peru. All but the Paracas Necropolis samples were part of technical conservation studies of the ancient South American textiles collections of the Michael C. Carlos Museum. Analysis of the dyes was carried out utilizing direct analysis in real time time-of-flight mass spectrometry (DART-MS) and paper spray MS. To validate these ambient ionization MS methods, the samples were further investigated using high-performance liquid chromatography (HPLC) with ultraviolet-visible diode array detection (DAD). These results show that ambient ionization MS methods are simple and fast for characterization of the general classes of dyes, e.g., plant reds vs. insect reds, and indigoids in blues and greens. Due to the myriad possible sources of yellow dyes and their tendency to undergo oxidative decomposition, positively identifying those components in these yarns was difficult, though some marker compounds and flavonoid decomposition products were readily identified by ambient ionization mass spectrometry.

Highlights

The ancient weavers of Peru are known for their complex multicolored textiles, preserved in burial contexts primarily due to the dry and cold conditions of these high-altitude locations
We sought to identify the colorants present in the yarn samples from the ancient Peruvian textiles to add to the existing body of knowledge about the dyes used over the time periods described above, ideally to determine the relationships between the primary and secondary colors
We have shown the characterization of the dyes present in both the primary and secondary colors found in ancient Peruvian textiles from multiple cultural periods over a span of nearly 1800 years, including the Paracas Necropolis, the Nazca, the Wari, the Chancay, and the Lambayeque

Summary

Introduction

The ancient weavers of Peru are known for their complex multicolored textiles, preserved in burial contexts primarily due to the dry and cold conditions of these high-altitude locations. These textiles, which span a wide range of time and geography across the Andes, have long been admired for their intricate workmanship and complex designs. In some cases, identifying a colorant identifies the dye source, as in the case of carminic acid, which is indicative of cochineal from Dactylopius coccus and various subspecies. Other colorants, such as luteolin and quercetin, are found in numerous plant dye sources. Characterizing the dyes in textile samples to identify the colorants may or may not identify the dye sources that were used by their makers

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