Archaeological Conservation Program
Highlighting Our Work with Archaeological Projects

The Archaeological Conservation Program [ACP] seeks to improve the partnership of conservation and field archaeology through an innovative combination of opportunities based in the Objects Laboratory at the Smithsonian Center for Materials Research and Education [SCMRE]. The program offers advanced internships in archaeological conservation, carries out conservation work in conjunction with archaeological projects, pursues in-depth technical study of archaeological materials at SCMRE, and provides other educational offerings focusing on conservation issues in both conservation and archaeology venues.

Several new collaborations marked the Archaeological Conservation Program's activities in 2003 (Fig.1). The primary addition to the roster of participant sites was the San Bartolo Archaeological Project (Petén region, Guatemala), with conservation teams involved during both the winter-spring field phase and the summer laboratory phase in Antigua. During the summer work period, conservation assistance was also provided to the La Casa de las Golondrinas Archaeological Project (Antigua Valley, Guatemala).

The ACP conservation team members this year included Batyah E. Shtrum (a graduate student from the University of Delaware/Winterthur art conservation program), who took part in San Bartolo's field phase [Fig.2]. Caitlin R. O'Grady and Kristina Martin (graduate students in conservation from New York University's Institute of Fine Arts and Erfurt's University of Applied Sciences [Germany] programs, respectively) spent the summer in Antigua working principally with the San Bartolo project, and also assisting the La Casa de las Golondrinas project [Fig.3].

San Bartolo Archaeological Project

San Bartolo had been an unknown site until March 2001, when William A. Saturno (University of New Hampshire and Harvard University's Peabody Museum), along with several guides, stumbled upon it in a remote part of the lowland jungles of the Petén region. What caught his attention were glimpses of elaborate mural paintings within one of the overgrown ruins - exceptional for both their quality and apparently early date (ca. 100 AD). Under Saturno's direction, the San Bartolo Archaeological Project returned in June 2001 to undertake a site reconnaissance, followed by test excavations in June 2002 and then a full-scale field season in 2003. These excavations are showing that the pyramid complex, with which the painted room is associated, and other prominent clusters of structures are at the core of what had been an impressive pre-Classic settlement, beginning perhaps as early as 1000 BC and terminating in the Early Classic period (by 500 AD).

Conservation was envisioned as a component of the archaeological project since its inception, with mural conservators Leslie H. Rainer and Angelyn Bass Rivera quickly incorporated into the team to carry out in situ wall painting stabilization. The artifacts conservation component, phased in once the wall paintings component had been established, was implemented during the 2003 season.

The primary goal of our site visit in March was to gather information about the kinds of artifacts that were being excavated, and the site conditions and excavation procedures that might influence their state of preservation. This information would help us prepare for the project's summer laboratory phase in Antigua, a Colonial-period city near Guatemala's capital, where all materials would be brought at the end of the excavation period. Our schedule was also coordinated with the wall paintings conservators' work at the site, to give us a chance to become familiar with these activities.

During the field visit, the artifacts conservators carried out in situ treatments, including the reconstruction of a damaged stone monument (Fig.1, Fig.4). It was a pot-bellied seated figure carved from a boulder, which appears to have been visited for ceremonial reasons, based on the impressive heap of smashed ceramic vessels found around it. These ceramics date to the Late Classic period, when the site no longer appears to have been occupied. Some of the sherds from this deposit can still be seen in the walls of the trench (Fig.4). The ACP conservation team also continued stabilizing some of the stuccoed walls at the site, including exterior portions of the Mural Room (Fig.5).

During the summer, conservators joined the project team members in Antigua for the laboratory phase (Fig.6). Painted stucco wall fragments collected in 2001, 2002 and 2003 from tunnels and excavation areas associated with the Mural Room were conserved and rehoused for protective storage (Fig.7). The conservators also began the long process of reconstructing the intentionally smashed ceramics from the ceremonial deposit, for more detailed information about stylistic types and number of vessels brought to the site. Ceramics reconstruction was of particular interest to the archaeologists, and a workshop was presented to all the team members covering topics such as selection of appropriate conservation materials and basic reassembly techniques.

La Casa de las Golondrinas Archaeological Project

A dramatic 30 meter wall of volcanic tuff provides the setting for the largest rock art site in the Guatemalan Highlands, near Antigua (Fig.8). More than 100 painted motifs distributed over the surface may date to the Postclassic period (ca. 1300 AD) but artifact deposits reflect visitation extending from the Pre-Classic (beginning ca. 1000 BC) to the Post-Conquest period. Archaeological investigations at the site, directed by Eugenia J. Robinson (Montgomery College, Rockville, Maryland, and the Centro de Investigaciones Regionales de Mesoamérica, Antigua), have focused on documentation of the paintings and test pits of ceremonial deposit locations near the rock face.

During the summer work period, ACP conservation staff had an opportunity to visit the rock art site and the local storeroom, where some of the finds from test excavations are temporarily stored. One of the most remarkable of these was a special offering of weaving implements placed in a large ceramic jar, dated to about 1300 AD. Archaeological objects made of organic materials rarely survive in climates that are neither extremely dry nor extremely wet. As a result, the palm nut spindle whorls and gourd bowls with textile remnants found in this deposit form a particularly unusual and rich assemblage for study. Their damaged and fragile condition, however, meant that they needed to be well protected in storage. Using stable synthetic materials, ACP interns produced some customized storage containers that would allow the objects to be easily viewed and at the same time safely housed (Fig.9).

For further reading:

The discovery of the San Bartolo site and its extraordinary murals was reported in the April 2002 issue of National Geographic and on the web at

Information about the San Bartolo Archaeological Project can be found on its web site,

A report about the rock art at La Casa de las Golondrinas by Eugenia J. Robinson is available on the web site of the Foundation for the Advancement of Mesoamerican Studies, Inc. [FAMSI], at

For more information, contact the author: Harriet F. (Rae) Beaubien