This European Standard specifies the characteristics and performance requirements of masonry units manufactured from natural stone the width of which is equal to or greater than 80 mm, for which the main intended uses are common, facing or exposed masonry units in loadbearing or non-loadbearing building and civil engineering applications These units are suitable for all forms of coursed or random masonry walling, including single leaf, cavity, partition, retaining and the external masonry to chimneys. They can provide fire protection, thermal insulation, sound insulation and sound absorption. This European Standard includes natural stone masonry units of an overall non-rectangular parallelepiped shape, specially shaped and accessory units for internal and external application. It defines the performance related to e.g. strength, petrographic description, density, porosity, dimensional accuracy, thermal conductivity, water absorption, and frost resistance and provides for the !assessment and verification of constancy of performance (AVCP)" of the product to this European Standard. The marking requirements for products covered by this European Standard are also included. This European Standard does not cover storey height panels, natural stone for paving, chimney flue linings nor units intended for use as damp proof course.