Repair materials for sulphatically and hydraulically bonded masonry

Introduction In several parts of Germany, at least until the late 19th century, many buildings made of artificial stone (e.g., bricks) and natural stone (e.g., slate, limestone, sandstone, gypsum rock) were bonded with gypsum (or gypsum-based) mortar. Particularly in Thuringia, Saxony-Anhalt, Lower Saxony, Hamburg, Bavaria and Baden-Wiirttemberg, such mortar was in commonplace use due to the local natural occurrence of gypsum and advantageous means of transport (e.g., by water to Hamburg). Albeit, pertinent examples can also be cited for Berlin, Hesse, Mecklenburg-Vorpommern and Schleswig-Holstein. Prominent examples of gypsiferous masonry include the main structure of the Anna Amalia Library in Weimar, the Lubeck Cathedral, the Church of Saint Catherine in Ham-burg, St. Mary's Church in Liibeck and Runneburg Castle in Weissensee [1],.