Why Did Red Ereño Limestone Go Red? Linking Scientific Knowledge and Geoheritage Story-Telling (Basque Country, Spain)

Abstract Red Ereño is a red-stained ornamental and construction limestone with characteristic white fossil shells. Although exploited since Roman times, marketed worldwide that the rock itself its outcrop areas have been included in geological heritage inventories, origin of reddish colour remained unresolved. The aim this work to deepen scientific knowledge as basis for understanding characteristics stone make information available geoconservation actions. mineralogical petrological study, mainly based on optical electron microscopy, X-ray diffraction, magnetism paleomagnetic techniques, concluded red-staining mineral pigmentary hematite. Moreover, analysis stated hematite precipitated after sedimentation but prior burial diagenesis before alpine inversion. Based palaeomagnetic studies, it can be mineralisation occurred during Late Cretaceous. This illustrates how research potential provides key geoconservation.