Auteurs : Lionel Dupret http://popups.lib.uliege.be/3041-5527/index.php?id=647 Publications de Auteurs Lionel Dupret fr 0 Différenciation des hématites oolithiques à partir d’observations macroscopiques non destructives : essais de comparaison des matériaux ordoviciens normands et dévoniens belges http://popups.lib.uliege.be/3041-5527/index.php?id=703 The analysis of ochre archaeological artefacts could be realized without its destruction. The aim of this study is to identify macroscopic characteristics to distinguish on these artefacts oolitic ironstones (OIS) from different origins, in this case norman ordovician and belgian devonian ones. Despite frequent difficulties in observations, it shows that the only relevant criterion in order to determine correctly the origin of OIS lies in the form of the ooids. Other criterions, as the size or the sorting of ooids, or the colour of the cement, alone are not discriminating. The comparison of observations on several objects, both on raw materials or on polished surfaces, should enable to propose a differential diagnosis. Fri, 29 Nov 2024 14:17:18 +0100 Fri, 29 Nov 2024 14:28:46 +0100 http://popups.lib.uliege.be/3041-5527/index.php?id=703 Premières données sur l’exploitation de l’hématite en Basse-Normandie durant la Préhistoire récente : ses contextes archéologiques et géologiques, son insertion dans le cadre de la néolithisation de l’ouest du Bassin parisien http://popups.lib.uliege.be/3041-5527/index.php?id=636 The oolithic ironstones (OIS) are one of the main sources of prehistorical red dye. The geological occurrences are well known in Basse-Normandie because they were used into mining industry. The fields are often disappeared today and the samples we took are not always representative. This paper summarizes the main characteristics and the genesis of these oolithic levels. They has been deposited on a subtidal open shelf, exposed to tidal wave activity and located south of the infra-Cambrian continent. The presence of oolithic ironstone artifacts in some archeological sites is an evidence of their use as raw materials for prehistorical red ochres. To compare the geological materials and the archeological artifacts, we set up a protocol of analysis including macroscopic observations, petrography, geochemistry and color analysis. Furthermore, we integrated samples from Belgium and Germany, potentially incriminated in long-distance interchanges in Western Europe. Fri, 29 Nov 2024 13:10:40 +0100 Fri, 29 Nov 2024 14:26:18 +0100 http://popups.lib.uliege.be/3041-5527/index.php?id=636