EXARC Journal (May 2021)
Fresco Mixtures with Dried Lime Plaster: Cameron’s Experiments Revisited
Abstract
During the Bronze Age, craftspeople of the eastern Mediterranean reused fragments of mortars as aggregates in lime mixtures. In the 1970s, Mark Cameron experimented with the techniques of Minoan fresco preparing and painting. His experiments showed that it is possible to create mortar by mixing lime plaster with dried powdered lime plaster, and by mixing dried powdered lime plaster with water. These mixtures became the basis for the experiments presented in this paper. Fragments of mortar can be used as aggregates in a lime mortar, but only as a small part of the aggregates of a mixture. Mixing dried powdered lime or crushed thin shards of mortars with water produces granular pastes, which can be spread and painted. This technique can be used to recycle mixtures in order to practice spreading mortar, but not to create works that will stand the test of time. Dried lime plaster can be used as an aggregate in mixtures, including those used in fresco. The material behaves better when it is used in a powdered form. Analyses of the mortars of ancient frescoes must be exhaustive and take into account the fact that ancient craftspeople might have used unusual techniques.