Red Ereño: an Ornamental and Construction Limestone of International Significance from the Basque Country (northern Spain)

Red Ereño is widely prized as an ornamental and construction stone for its intense red micritic matrix, contrasting with the white rudist fossil shells it contains. Quarried since Roman times (first century) in the localities of Ereño and Gautegiz Arteaga, Red Ereño is a recognised limestone and has been widely used in architecture ever since. It was utilised extensively in the Basque Country and is characteristic of the urban landscape of several of the region’s most important cities, including Bilbao and Gernika (Guernica). It has also been used in many monumental and other buildings throughout the Iberian Peninsula. Red Ereño limestone has also been exported to the Americas and Italy, the most significant example being its use in the flooring of St Peter’s Basilica in the Vatican. This paper summarises the main features of Red Ereño as a candidate for consideration as a Global Heritage Stone Resource (GHSR). This recognition will be important for future research and restoration works of existing heritage buildings.