ABSTRACT
Introduction Plastering, based on lime, was brought to Britain by the Romans. In Britain it was originally used to strengthen and seal surfaces and in the case of combustible materials to afford some fire protection, but by the eighteenth century its value as a decorative finish had been appreciated. The use of gypsum plaster both as a sealant and as a decorative material by the Minoan civilisation is well documented, and current UK practice is now based on gypsum (hydrated calcium sulfate), rather than lime. Gypsum is mined from geological deposits produced by the gradual evaporation of lakes containing the mineral; there are extensive reserves within the UK, mainly in the North of England, but also in the East Midlands.
