Contribution to studies on Roman wall painting materials and techniques in Greece: Corinth, the southeast building

A batch of 14 fragments of Roman wall painting brought to light during the excavations of the so-called "Southeast Building" in the Forum of Corinth were investigated in order to characterize the materials of both support and paint film and thus to identify the technique used for their execution. The fragments do not represent homogeneous samples but each of them may come from a different building phase or decoration. Therefore, they were all systematically subjected to the same analytical program. Results of analyses carried out on the support grouped the fiagments in three main classes, plus two distinct fragments whose features are reported in detail as well as those of the overlying paint film. The three groups are inferred to belong to the same building phase, mainly on the basis ofthe similar features of ground plaster (a). Differences in plaster finish coat (b), together with the dffirent technique of execution displayed by the paint films, may reflect the different locations or purposes of the paintings represeflted by the fragments of groups 1 and 2. The fragments of group 3 and fragment 5 display an uncommon, smooth red plaster coat (c). Fragment 5, however, belongs to a subsequent event since it re-uses in coat (c) clasts of the equivalent coat ofthe fragments of group 3. The Egyptian blue of the paint films was compared with a grain of rough blue pigment (sample 15) found together with the fragments. In all of them Egyptian blue corresponds to cuprorivaite, with almost stoichiometric composition. A yellow Pb,Fe(Sb,Zn) arsenate, probably representing an unintentional arfficial by-product, is also described.