Renaissance for artisanal mortar
(PHYSorg.com Archaeology & Fossils)

To adapt mortar to new building materials and industrial methods, the content in walls and plaster changed during the 20th century. The change meant that knowledge of historical materials and methods for producing mortar were lost. New research at the University of Gothenburg reveals that historical binding agents and mortar can be produced and used in present-day plaster restorations.