Fresco and Lime‐paint: An Experimental Study and Objective Criteria for Distinguishing Between These Painting Techniques

Abstract

Identification of the painting technique adopted by an artist is often debated in studies on the characterization, restoration and conservation of mural paintings. However, objective criteria to identify the two main lime-based painting techniques, fresco and lime-paint, have not yet been systematically verified on replicas. Replicas were painted following both fresco and lime-painting techniques. A comparison of microstratigraphic sequences and distribution of chemical elements reveals systematic differences between the two techniques, providing objective distinguishing criteria. Samples from the Abbey of Chiaravalle (Milan, Italy) and Pompeii were also analysed, and the results were compared with experimental data to validate the recommended criteria.

Wall Paintings from the Roman Emona (Ljubljana, Slovenia): Characterization of Mortar Layers and Pigments

“…), or inorganic (lime water), sometimes also called lime paint (Piovesan et al . ) or even lime secco (Weber et al . ).…”

Analytical study of the XIV century wall painting and lime mortars in the "St. George" church in Staro Nagoričane, Republic of Macedonia

“…2 a-c) indicates painting on dry plaster (lime technique or mezzo-fresco) [9][10][11]. On other hand, the penetration of the pigment grains into the plaster, as is shown in Figure 2d and e, could be ascribed to the thorough carbonation process [8,9] which is typical for a painting on wet plaster (buon fresco) [8][9][10][11].…”

“…On other hand, the presence of calcium carbonate in the paint layers implies the use of some types of fresco techniques such as buon fresco (true fresco) which refers to painting on wet plaster with water-mixed pigments and the lime-painting technique, elsewhere also defined as mezzo-fresco, ascribed to painting on dry or almost dry plaster using pigments mixed with slaked lime [9,[11][12][13]. The discrimination of these two techniques is a debatable point since both techniques are represented by lime binding medium; the corresponding micro-stratigraphic images exhibit very similar features.…”

“…Regarding the painting technique, two characteristic features of the cross-sectioned samples were considered as relevant indicators of the used techniques, which are: the nature of the binding medium and the paint adherence to plaster [8][9][10][11].…”

The Polychrome Sinopia of Roman Mosaic at Lod (Israel): Pigments Characterization and Microstratigraphic Study

“…This, as described in Piovesan et al (2012), is the result of the carbonation process occurred on the surface of a mortar during the hardening, and clearly indicating that the painting was realized following the fresco technique. Therefore the particles of pigments were spread on the fresh mortar of the sovranucleus only diluted in water.…”