The colour of ceramics from Bell Beaker contexts in NW Spain: relation to elemental composition and mineralogy

摘要: Abstract In this paper we characterise the mineralogical and elemental composition colour (CIELab space) of Bronze Age pottery sherds from NW Spain, using X-Ray diffraction, fluorescence reflectance spectroscopy, respectively. For half samples also determined content in secondary iron oxi-hydroxides (sFe, extracted with dithionite–citrate), atomic absorption. The aim investigation was to study relationship between composition, explore intentionality resulting colour. Samples had a low luminosity were located quadrant CIELab space ranging red yellow (hab: 0–90°), showing hue variability but wider range variation chromaticity. terms they showed large (12 different minerals identified) chemical (from acidic/felsic basic-ultrabasic/mafic compositions) variation. A principal components analysis parameters demonstrated that (L*) depends on organic matter (OM) lesser extent sFe content. Chromaticity (C*ab) content, felsic/mafic relative OM while (hab) is only related mineral phases. We verified these general trends differ certain depending whether contains amphibole or not: effect L* b* (yellowing) C*ab detected for without amphibole, an increase felsic relation mafic has more decisive chromaticity amphibolic clays. Thus, seems result interplay i) original raw material/clays, ii) compositional factors (overall -felsic vs mafic-, content), iii) interactions processing (sFe firing conditions controlling yellowing). interpret there intentional selection materials (felsic mafic) their (addition oxides matter) control over order give vessels specific