A geochemical and mineralogical approach was used to analyze 3rd millennium BCE pottery from Southeast Lithuania that is attributed to the foreign Corded Ware Culture and local hunter-gatherers. SEM-EDS, XRF, XRD, and FTIR were used to study the peculiarities of the pottery and to develop hypotheses about the raw material and technology choices present. The amounts of ten major elements in the bulk and clay matrix compositions (XRF, SEM-EDS) and eleven trace analytes in the bulk compositions (XRF) were compared with the Clarke values and tested to highlight the significance (Mann–Whitney U and Wilcoxon Matched Pairs Tests) of the differences in the elemental quantities between the clay matrix and bulk compositions, and between the lighter and darker clay matrixes. These also revealed the advantage of Ward’s clustering method using the City-block distance of bulk compositions as a tool for inter-correlating ceramics in attributing them to specific communities and locations. The XRD, FTIR, and SEM-EDS mineralogical analyses indicated a predominance of iron-rich illite clay, quartz, and alkali feldspar, in addition to very low to medium firing temperatures. All of the pottery samples consisted of hydromicaceous clay from local Quaternary glacial sediments that contain weathered granitoid fragments.

The current research paper presents the results of the first regional assessment of sediment contamination by dioxins (polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs)) in the south-eastern part of the Baltic Sea (Lithuanian and Polish marine areas) during the periods of 2014 and 2019–2020. In total, 143 surface and core sediment samples were taken of existing offshore dredged-soil-disposal sites in the area of the former shipyard in the Port of Gdynia (Poland), as well as in a profile from the nearshore to the deeps of the Gdansk basin, following the natural pattern of sediment migration in the region. The obtained results indicated wide variation in both the total content of the investigated compounds as well as the profiles of congeners, indicating the likely sources of their origin. Based on the obtained concentration characteristic profiles of the congeners, we determined the amount of dioxins and the likely sources of their origin in the Gdansk Basin. The profiles showed elevated contents of octa- and hepta-chlorodibenzodioxins (OCDD and HpCDD) in the sediments, while the fractions of most other toxic congeners were considerably lower. The domination of OCDF in the spectrum of the studied PCDFs suggests the possible contribution of industrial processes. The obtained results have filled the gaps in our knowledge while providing a perfect background for more detailed discussions concerning the accumulation of dioxins in surface sediments from the south-eastern part of the Baltic Sea.

Geochemical indices used to identify the emerging anomalies of potentially harmful elements in topsoil depend on background values (BVs). For urban sites, it is reasonable to estimate native BVs through the targeted selection of peri-urban sampling sites or by distinguishing a useful background subset (BS) within the peri-urban dataset. Here, the goals were to examine the influence of Quaternary deposits on various types of topsoil variables, identify the variables most helpful for cluster analysis intended for the choice of background subset (BS), and compare background values (BVs) based on different background subsets. Composite topsoil samples from a peri-urban area were used for the determination of the following variables: contents of 26 elements and components of the bulk mineralogical composition, as well as the sand, silt, and clay fractions and loss-on-ignition (LOI) at 550 °C and at 950 °C. Although Quaternary lithology influences topsoil elemental contents or granulometric fractions, percentages of illite, kaolinite, orthoclase, quartz, albite, dolomite, and LOI at 550 °C, the choice of BS, according to it, is not recommended, as BVs based on topsoil texture are superior. However, cluster analysis using topsoil fractions < 2, 63 μm or the contents of Al, Fe, K, Ti, Ga, Nb, Rb, and Si are preferable. It is recommended to use these reference variables for the selection of BS.