Stylolitic limestone, the stone of choice for ancient sanctuaries and temples, southwestern Peloponnese, Greece

Abstract An Upper Cretaceous limestone was the stone of choice for classical Greek buildings and temples within the Pindos belt of the western Peloponnese. Knowledge of its properties at the Sanctuary of Zeus (Mt. Lykaion) is applied here to the Temple of Apollo Epikourios (Bassae) and the Arcadian Gate (Messene). Because of severe contortion and weathering, it was previously concluded that this bedrock was not the stone used at Bassae. Overlooked was the presence and weathered condition of its pervasive stylolites, which are closely spaced (cm‐scale) brain‐suture‐like surfaces resembling bedding laminae along which calcite dissolves and clay residue accumulates. The stylolites convey a false impression that the limestone is thin bedded and prone to splitting. Stylolites form as a response to stress during burial compaction and/or tectonic compression. Released calcium carbonate reprecipitates as calcite veins. The presence of the clay residue accounts for the severely weathered condition of outcrops and blocks. The suitability of this stone as a building material derives from cohesion acquired through bonding of interlocking stylolites and sealing by calcite veins. Its underdeveloped jointing explains how the megablock lintel of the Messene gate was geologically available. Opportunities are presented to evaluate stylolites at other geologically suitable archaeological sites.