Sprawozdania Archeologiczne 74 nr 1 (2022)

Until recently, all the erratic flints found at the Stone Age sites in the upper part of the Odra Valley were identified with silicites from the Baltic Sea. The age of Baltic flints is associated with the Uppermost Cretaceous, more precisely with the Maastrichtian or Palaeogene. However, it turned out that among these rocks, there are also silicites that are of different ages and origins. They were first found in outcrops of sands and gravels around Opole-Groszowice. So far, these flints have been distinguished in archaeological assemblages but they were usually regarded as imports from the Cracow-Częstochowa Jurassic Plateau. The petrographic analysis proves that these silicites of brown colour are of the Jurassic age. They entered the glacial sediments via the lobes of the Drenthe glaciation. They were used in the same way as raw materials of Baltic origin. In this paper, we show some examples of Palaeolithic and younger sites, where artefacts made of brown silicite occurred.

il. ; 25 cm

ill. ; 25 cm