Sustainable solutions: Water-based consolidants for the treatment of low-fired ceramics

Céline Wachsmuth


This research is being conducted as a thesis project within the UCLA/Getty Master’s Conservation Program. Low fired ceramics are ubiquitous in cultures around the world and yet little literature exists on consolidation options for treating their often powdery surfaces. Using mock-ups, I am comparing water-based consolidants for their use in surface consolidation of such low-fired ceramics. The goals include evaluating more sustainable options for treatment not only for the benefit of the environment, but also for the health of conservators. Water-based consolidants may also benefit field work since solvent availability and hazardous material procedures are often limited. While controlled experiments give conservators an empirical framework for understanding aspects of the materiality of the heritage items we work with, such investigations are only one factor in the conservation decision-making process. The various cultural contexts of these ceramics are just as much, if not more, of a guiding factor in treatment decisions. To that end, I am working with Landis Smith, Projects Conservator at the Museums of New Mexico Conservation Lab/Museums of Indian Arts and Culture. She is introducing me to potters from two or three pueblos with whom I am beginning to engage in conversation about what is most important to them about their pottery as well as their thoughts on conservation intervention.

To learn about current use of consolidants for low-fired ceramics, I surveyed conservators in English, French, and Spanish. Current responses indicate prevalent use of Paraloid B-72 for consolidation. Few conservators currently choose to use water-based solutions.
Five consolidants were chosen for testing: Methylcellulose, Ethulose, Jade 403, Acrysol WS-24, and Aquazol 200. These were chosen based on a literature review and conversations with some archaeological conservators. Due to the COVID-19 pandemic, I pivoted the testing from the UCLA/Getty Program labs to my Los Angeles residence. Although it was not planned, the low technology set-up more closely replicates the archaeological field experience. To make the sample mock-ups, I used raw materials from New Mexico Clay and fired them in an electric kiln at approximately 730°C. I used easily accessible materials to roughen the ceramic sample surfaces and craft two aging chambers – one for high temperatures and one for high relative humidity in attempts to recreate potential storage environments. Each consolidant was tested at two different concentrations and applied by brush. The samples were split into three groups; a control and one set for each of the aging chambers. They were photographed using a DSLR camera along with detail shots of the surface using a USB DinoLite Microscope. I performed a simplified tape test on the surfaces and used a portable FieldSpec 3 fibre optic reflectance spectroradiometer to take color measurements. Preliminary results suggest a low concentration solution of methylcellulose as a possible alternative to solvent based solutions. Initial discussions with potters underline the importance of collaboration and making a treatment plan that respects the community’s desires and intended use for a pot.

This research is partially supported by the Foundation for Advancement in Conservation’s Take a Chance Grant.

2022 | Los Angeles | Volume 29