Jesuit Mission Roof Tiles of South America

The Jesuit missions (reducciones) founded among the Guaraní of present-day Paraguay, Argentina and Brazil from 1609, and later among the Chiquitos of eastern Bolivia, produced their own fired clay roof tiles on a large scale. Tile roofs on churches, colleges and Indigenous houses became one of the defining features of mission towns, several of which are now UNESCO World Heritage Sites.

From straw to tile

Early mission buildings were roofed with straw. A 2016 archaeological study by María Victoria Roca of the decorated tiles of the church of Santa Ana in Misiones, Argentina, summarises the history. Historians date a second building phase, about 1641 to 1695, as the era of churches and Indigenous houses with tile roofs. Tiles were adopted partly as protection against fire after raids by slavers from São Paulo, and later Jesuit instructions, from 1714, called for straw roofs to be replaced with tile. During the second term of the provincial Luis de la Roccafiorita (1722 to 1726) it became the rule that each mission should have its own tile workshop.

Making the tiles

According to the sources Roca reviews, clay was kneaded and left to rest for days, trampled by cattle and oxen, pressed into moulds, dried on a rack and fired in kilns. The Jesuit Anton Sepp described three kilns, each holding about 4,000 tiles. Tiles from San Ignacio Miní measure about 46 to 55 cm (18 to 22 in) long, 19 to 22 cm (7.5 to 8.7 in) wide and about 1 cm (0.4 in) thick. Roca notes two colonial traditions in the region: Spanish curved tiles with a parabolic profile and Portuguese tiles with a semicircular profile.

At Santa Ana, 67 decorated fragments were recovered, almost all from inside the church. Most carry a border with a crescent motif at one end, and the author concludes that decorated tiles covered a large part of the church roof, not only the edges. Some show traces of burning from the destruction of the mission in the early 19th century. When the explorer Juan Bautista Ambrosetti visited in 1894 the roofs had collapsed.

Chiquitos

In the Chiquitos missions of Bolivia, built in the 18th century, the structure works the other way round from European masonry churches. A wooden skeleton of columns set into the ground carries the tiled roof, which was built first; the adobe walls carry no load. Wide porches and low eaves protect the walls from tropical rain, and roof and floor tiles came from local tile works. The churches, restored from 1972 under the architect Hans Roth and later local teams, were inscribed by UNESCO in 1990.

World Heritage

• Jesuit Missions of the Guaranis (Argentina and Brazil), 1983
• Jesuit Missions of the Chiquitos (Bolivia), 1990
• Jesuit Missions of La Santísima Trinidad de Paraná and Jesús de Tavarangue (Paraguay), 1993