EN
Ten pieces of iron concretions were found in two features from the 11th –12th century. Their limited number gives a cause for doubts that this raw material could be technologically processed for the raw iron. No equipment or other pieces of evidence of metallurgical activity was found in this settlement. For this reason is such production of iron in rural settlement little probable. More real could be the consideration that the iron concretions, which were found, were picked in order to produce red pigment which was used for staining. The results of mineralogical study of the Fe3+-rich concretions by optical and back-scattered electron image microscopy (BSE ), electron microprobe (EMPA) and X-ray diffraction analysis (XRD ) indicates a presence of hydrated and silicified goethite, Fe3+O(OH ), as the main component of the concretions. The iron content of the concretions attains 72 to 80 wt. % Fe2O3 and 3.5 to 5.2 wt. % SiO2. Textural and geochemical data support the natural origin of the iron concretions, probably by sedimentary precipitation of goethite from Fe-bearing solutions in wet swamp or lacustrine environment.