AIC's 52nd Annual Meeting

In the spring of 2023, a team of local conservators and outside technicians performed conservation and stabilization work in the main cupola of San Xavier del Bac for the first time in 29 years.

San Xavier’s spectacular baroque interior and ambitious dome and vault construction make it a premier example of Spanish Colonial art and architecture. Its interior walls are adorned with polychromatic murals dating to 1797, executed in fine detail and applied a secco atop a gesso preparation layer, layers of lime-sand plaster of varying granulometry and thickness, and a brick support. Paints were made with imported pigments including vermillion, prussian blue, and orpiment–a significant expenditure for a church at the frontier of the Pimeria Alta in the late 18th century; Rutherford Gettens looked at some of these paints. San Xavier del Bac exists within a unique contemporary cultural context: it is an active church, owned by the parish and staffed by the Franciscan Friars, located within the tribal community of Wa:k in the San Xavier District of the Tohono O’odham Nation. Church management handles day-to-day operations, while conservation and preservation activities are funded and coordinated by the nonsectarian nonprofit Patronato San Xavier. Within the tribal community, there is a strong sense of cultural ownership; tribal members are appointed as church bell ringers, comprise Feast Committees, and take on other roles related to the church.

The first major conservation campaign took place between 1990 and 1997 by European and East Coast-based conservators, who cleaned and stabilized the wall paintings and statuary using modern methods and materials of the time. Four apprentices from the local tribal community were trained to assist. Since then, a local team, two of whom were part of the 1990s crew, have directed conservation work. Informed by decades of observation of the building’s unique conditions, they refocused conservation protocols on the use of traditional materials and methods. Given the complex nature of the building along with its role as an active church, performing routine, sustainable care is an ongoing challenge, but one now directed with input from the local community.

This session will recount the collaborative process along with the means and methods used while revisiting the main cupola, which sits 53 feet above the church floor. The cupola was identified as a priority given the presence of large cracks and crack systems, history of water infiltration, soiling, biodeterioration, aged original paint and coating, and aged restoration fills, all in a harsh desert with minimal preventive maintenance. The large scope of work–both surface and structural– accessibility challenges, and a desire to limit disruption of church functions led us to seek additional skilled hands to expedite the project. This time, our local team trained and oversaw a group of outside technicians, students, and skilled volunteers to complete the work, all of whom were unfamiliar with the specifics of the site. Progress was shared with more than 100 members from the tribal and religious community through a series of tours and discussions.