According to Cowden and Wessel in “Twentieth Century Building Materials,”
“Cast stone is a highly refined form of concrete made from portland cement, fine and coarse aggregate, and water. Executed as veneer, block, or ornament, cast stone typically simulates evenly veined and colored stones. Used extensively during the late nineteenths and early twentieth centuries, cast stone was produced in a wide range of colors and textures. By the late 1920’s numerous formulations of varying comprehensive strengths were used to simulate natural stone.
The conservation of cast stone is often related to problems that begin with historic manufacturing techniques. Many causes of deterioration are related to techniques that used distinctive aggregates, varied grading profiles, and pigments to create specific surface colors and finishes. When proper standards for proportioning were ignored, cast stone products sometimes had unusually high porosity, which affected durability. Aggregates lacking suitable durability were also used frequently, and these can accelerate weathering processes.”
For more information, refer to the text sources below.
- Cowden, Adrienne B., and David P. Wessel. ”Cast Stone.” In Twentieth Century Building Materials, edited by Thomas C. Jester, 87-93. New York: McGraw-Hill Co., 1995. “Preservation Brief 42: The
- Maintenance, Repair and Replacement of Historic Cast Stone”. National Park Service, http://www.nps.gov/history/ hps/tps/briefs/brief42.htm (accessed April 25, 2010).