Study of forge slags from the Roman site of Forua (Bizkaia)

The archaeological site of Forua (Bizkaia) corresponds to an iron production centre of the Roman period (1st–3rd centuries AD). The distribution of the workshops joint to the type of slags indicates that correspond to a set of forging furnaces. The micro-textural and mineralogical features of the studied materials allow us to differentiate three groups, two of them correspond to forge slags, while the other group represents the ore mineral. These two types of slag indicate different stages in the production of iron from ferriferous spongeEl yacimiento arqueológico de Forua (Bizkaia) corresponde a un centro de producción de hierro en época romana (s. I–III). La distribución de los talleres junto con el tipo de restos encontrados indican que se trata de un conjunto de hornos de forja. Las características mineralógicas y microtexturales de los materiales ferruginosos estudiados permiten diferenciar tres grupos, dos de ellos corresponden a escorias de forja, mientras que el otro representa la mena de hierro. Los dos tipos de escorias indican estadios diferentes en la obtención del hierro a partir de la esponja ferrífer

Mineralogical Characterization of Slags from the Oiola Site (Biscay, Spain) to Assess the Development in Bloomery Iron Smelting Technology from the Roman Period to the Middle Ages

The Oiola archeological site, located in the mining complex of La Arboleda (Biscay, North Spain)was an important iron smelting center from the Roman Period to the Middle Ages and even in more current times (19th–20th centuries). Tap-slags and some plano-convex slags were identified as smelting slags. Samples were analyzed by optical microscopy, X-ray powder diffraction, scanning electron microscopy coupled with electron-dispersive spectroscopy and Raman microspectroscopy to perform a mineralogical and textural characterization. Additionally, thermogravimetric and thermodiffraction analyses were carried out to determine furnace operating temperatures. The mineral assemblage reflects furnace temperatures and cooling rates and the addition of quartz as the main flux to decrease the melting temperature of the iron ore. The comparison of slags from the Roman Period and the Middle Age reveals changes in the pyrometallurgical process through time.H.P.-B. would like to thank the PRE-2019-2-0138 PhD research grant of the Basque Country Government and the SGIker service at the University of the Basque Countr

Foruako (Bizkaia) aztarnategi arkeologikotik datozen erromatar garaiko forja zepa metalikoen karakterizazioa (I – III K.o. mendeak): Erromatar siderurgiaren inguruko ezagutza ekarpen berriak Bizkaian

[EUS] Foruako aztarnategi arkeologikotik datozen erromatar garaiko forja zepa metalikoen karakterizazioa, garai hartan indarrean zegoen siderurgiari buruzko ezagutza handitzeko asmoz