The performance of an induced calcium oxalate surface on globigerina limestone

Abstract

This paper contains the second set of results obtained from a research programme that consisted of an induced surface conversion of weathered Globigerina limestone from calcium carbonate to calcium oxalate and the prospects of it being used for the conservation of this stone. The first part of the research confirmed the formation of calcium oxalate even in salt (sodium chloride) contaminated samples. The second phase of the research showed that the production of calcium oxalate resulted in the formation of a more compact, more cohesive, and harder surface when compared to untreated samples, which showed no colour change, retained the original hydrophilic and wetting properties of the stone and also increased the stone’s resistance to acid attack (acetic and hydrochloric acid), and to salt weathering (using sodium sulphate).