1 INTRODUCTION

In the spring of 1996, six hand-drawn, 16th-century maps from colonial New Spain were treated in the Preservation and Conservation Studies (PCS) laboratories at the University of Texas at Austin (UT-Austin). These maps are part of the Relaciones Geogr�ficas Collection, which belongs to UT-Austin's Benson Latin American Collection. The treatment of the maps led to a prefatory study of their history and manufacture. A unique feature of all six maps is their colorful and slightly unusual paint. Fascinated by this, I decided to begin the study by researching colorants (pigments and dyes) common in 16th-century New Spain (Mexico). My research followed two courses: a literature survey of documented pre-Columbian and New Spanish colorants and a preliminary microscopic examination of specific colorants sampled from the six maps. The results of the literature survey and the pigment analysis are included in this paper.

The artistic style of the Relaciones Geogr�ficas (RG) reflects a blending of indigenous and European design. The supports of the RG maps are predominantly European rag paper, although there are maps on animal hides and indigenous amatl paper. Given the blend of artistic elements and the range of drawing supports, I presumed the paints and inks on the six maps would also be composed of Native and European pigments.

I was given permission to remove pigment samples from the six RG maps for analysis. Because of the limited budget and limited access to analytical equipment, the examination of the samples was primarily restricted to optical microscopic analysis. Prior to and during the pigment analysis, I conducted an exhaustive yet incomplete literature survey to provide background information on pre-Columbian and Spanish Colonial pigments and to guide the identification process. The review of the literature spanned many disciplines, including botanical, historical, and conservation sources on pigments and dyestuffs used for a variety of objects such as murals, textiles, and manuscripts.

The purpose of this article is to identify several of the colorants sampled from the six maps and to provide an overview of colorants used in 16th-century New Spain. I acknowledge the limitations of basing the identification of colorants on optical microscopic analysis; other analytical methods would provide more definitive results. In addition, I recognize that paint has other components, such as binders and grounds, and a thorough study would include these components. Therefore, this article is intended as a preliminary investigation of colorants in use during the early colonial period of New Spain and is by no means definitive. This article attempts to begin to understand the manufacture of early Spanish Colonial manuscripts and to contribute to the body of knowledge in the area of 16th-century New Spanish colorants.

The primary focus of this article is historical; however, it is potentially useful to conservation. For example, several colorants identified on the six RG maps and included in the literature survey are organic and therefore sensitive to changes in pH. By providing a general overview of pre-Columbian and post-conquest New Spanish colorants, this article can help guide conservators in their treatment and housing decisions for various types of artifacts (paper, objects, paintings). It seems that many colorants were widely used on a variety of materials. In fact, several of the colorants included in the literature survey have been identified previously on manuscripts, murals, ceramics, and textiles. While this article focuses primarily on manuscripts, its findings are potentially useful to other areas of conservation and other disciplines.