Characterization of mortars used for the construction of Saithidai Heroon Podium (1st century AD) in ancient Messene, Peloponnesus, Greece

The Saithidai Heroon Podium is a Mausoleum dated to the Roman Period located in ancient Messene, Peloponnesus, Greece. Its outer walls were constructed with porous and massive limestone blocks with no mortar in the joints. The core of the podium was filled by rock chips to angular boulders of sandstone, limestone, sand, gravel and earthy groundmass material. The groundmass is mostly composed of quartz and calcite, with minor amounts of clay minerals. Small, irregular lime lumps also occur, composed of authigenic euhedral calcite crystal assemblages and rare sub-microscopic quartz fragments, or rod-like CaO/SiO2-rich mineral assemblages developed in pore spaces on fine-grained authigenic calcite crystals. The mortar used for the filling material of the Podium was poorly homogenized semi-hydraulic lime derived from the calcination of pure limestone and siliceous limestone fragments, possibly the waste material from the finishing of the building blocks of the Podium walls.