This paper addresses one central issue of building stone research : an origin for calcium in gypsum formation in non-calcareous sandstones. A comparative study of Scrabo sandstone from outcrops and a 120-year-old building in central Belfast shows
how weathering has significantly altered the mineralogy. Preliminary results suggest that the occurrence of gypsum throughout the stone blocks is related to chemical reactions between a pore-filling mineral, actinolite, and sulphur oxides from urban
pollution. This study highlights the potential for future research into an internal mineralogical source of calcium for gypsum formation in building stones.
are compared with coastal dune sands, weathered building stone in Sydney, and soil material from an arid region, Broken Hill area, where numerous rock engravings are found. In all cases, comparisons are made between quartz grains : roundness of quartz grains
Two case studies are provided illustrating the manner in which photographic information relevant to assessing stone degradation may be used within a GIS. A time sequence of old photographs of the Judges Lodgings, Oxford, is located within a relative