Cuerda seca ceramic tiles: Explorations of resist formulas in various firing ranges

Abstract

In the 1920s and 1930s, residential and commercial buildings built in the popular Spanish and Moorish inspired designs throughout California were decorated with interior and exterior installations of cuerda seca art tiles. Decades later, replacement of damaged fabric, such as parts of tile schemes, forms a large part of the conservation and preservation ethic. How can preservation transpire if, in preservation, documenting details of aspects such as building conditions, materials, maintenance, etcetera are crucial and information about the materials, such as the cuerda seca resist formulations are unavailable?

The goal of this thesis was replication of the cuerda seca resist using various proprietary formulas, commercially available and mixed based on historic information and empirical research to discover suitable black line resist formulas. Various oils (linseed oil and olive oil), oxides (black iron oxide and manganese dioxide), and fluxes, (lithium carbonate, soda ash, and borax) were tested with appropriate clay bodies and glazes for three firing ranges: cone 06, cone 5 and cone10. In all of the firing ranges tested, successful formulations were found and would be suitable for conservators to use to preserve the cuerda seca art tiles that already exist and for artists to use in order to preserve the cuerda seca tradition.