Characterising and classifying archaeological plasters and mortars from Malta

Abstract

This dissertation aims at providing information on the make-up of local archaeological plasters and mortars based on two case studies, namely the Żejtun and San Pawl Milqi Roman villa sites where significant plaster, mortar and floors are preserved. The study reviews ancient and modern literature that discusses ancient plaster and mortar. Against this review, a method was chosen for the analysis and characterisation of plasters and mortars with the aim of knowing their structure and composition. This was accomplished through a series of techniques, including macroscopic and microscopic examination, Scanning Electron Microscopy with Energy Dispersive Spectroscopy, powder X-Ray Diffraction and thin sections. This study shows that there are similarities between what was produced locally and what ancient sources say about the materials and ratios that can be used to produce different mixes for plasters and mortars. Identification of fillers in wall plasters and mortars from Żejtun, brought to light the use of local materials. It has also been established that there is a correlation between the type of plaster and mortar and primary archaeological context.