The term calcestruzzo or astraki is used by Italian researchers working at Phaistos to describe a very hard, amorphous material that partially filled many of the rooms in the first palace, ultimately providing a solid platform for the construction of the new palace. These terms emphasize that it was a deliberately manufactured construction material, representing the earliest hydraulic cement in history, which, once in place, was as hard as the bedrock, hence the name astraki.
Some scholars have noted a similarity between this material and hard masses found elsewhere in Crete, suggesting that the astraki at Phaistos may have been solidified material formed by the coalescence of fallen wall debris. The closest example is certainly Vasiliki, where R. Seager posits that debris from the upper storey collapsed onto the ground floor walls and, due to the effects of fire and water, transformed into an almost petrified mass that was often deemed impossible to remove with a pickaxe. However, the excavators at Phaistos rejected this proposal, supporting their position with various scientific analyses (including SEM, EDX, XRD, and TG).
This presentation aims to address this issue by examining a series of monumental buildings excavated between 1900 and 2023 that have posed challenges for four generations of archaeologists. Their advanced construction techniques and architectural features -specifically the presence of a second floor- contrast sharply with their suspected Neolithic chronology. Detailed examinations of the exposed walls revealed that the ground floor featured stone walls with adobe linings and clay plaster, surviving to a height of 1.65 meters. The upper floor was constructed with mudbricks and rubble stones, bound together with a clay-lime mortar and apparently reinforced with horizontal beams.
This discovery on the one hand suggests that the horizontal timber-framed architecture, attested at Vasiliki around 2400-2200 BC, may date back approximately 2,000 years, as confirmed by multiple radiocarbon dates that place construction of buildings from Phaistos between 4250 and 4100 BC. On the other, it has permitted a microanalytical study of the astraki that aims to ascertain whether it resulted from a chemical process in which the timber present in the walls intensified fires, converting limestone into lime, or was artificially prepared as traditionally contended.
Wednesday, March 4, 2026, 12 pm EST, 7 pm in Greece, Zoom format
Please register for this lecture using the following link:
https://us02web.zoom.us/meeting/register/oFJoY5TNTT6se3L3M1xohw