Historical cements and deterioration materials: the case-study of the Palace of Knossos.

The Palace of Knossos in Crete is unique in its historical authenticity both in terms of
its importance as an archaeological site, as well as for the history of restoration. The
excavations begun at the end of the 19th century and were completed at the
beginning of the 20th century, uncovering a large built area with complex structures
and distinct functions, rich in objects and showing a careful choice of materials and
decorations. The need to preserve the excavated areas by the archaeologist Sir
Arthur Evans and his team, along with the desire to remake the grandeur of the
palace, originated in the reconstruction of some of the structures according to their
knowledge of the site and current concepts of the time, using the most modern
existing building materials such as cement.
Not assessing the merits of choices made by Evans, the fact is that these
reconstructions helped to give the dimension of the Palace and are in themselves
part of the history of the monument. Despite the durability and strength of cements,
they are not immune to deterioration, environmental conditions and increasing
number of visitors. This study aimed to the multi-analytical physical, chemical, and
mineralogical characterization of cements samples and decay crusts collected in
reconstruction zones of the Knossos Palace, to better understand the current
characteristics of these materials and possible relationship with deterioration
processes, contributing to future maintenance and preservation actions.