An interlaboratory comparison (ILC) was organised to characterise 87Sr/86Sr isotope ratios in geological and industrial reference materials by applying the so‐called conventional method for determining 87Sr/86Sr isotope ratios. Four cements (VDZ 100a, VDZ 200a, VDZ 300a, IAG OPC‐1), one limestone (IAG CGL ML‐3) and one slate (IAG OU‐6) reference materials were selected, covering a wide range of naturally occurring Sr isotopic signatures. Thirteen laboratories received aliquots of these six reference materials together with a detailed technical protocol. The consensus values for the six reference materials and their associated measurement uncertainties were obtained by applying a Gaussian, linear mixed effects model fitted to all the measurement results. By combining the consensus values and their uncertainties with an uncertainty contribution for potential heterogeneity, reference values ranging from 0.708134 mol mol‐1 to 0.729778 mol mol‐1 were obtained with relative expanded uncertainties of ≤ 0.007 %. This study represents an ILC on conventional 87Sr/86Sr isotope ratios, within which metrological principles were considered and the compatibility of measurement results obtained by MC‐ICP‐MS and by MC‐TIMS is demonstrated. The materials characterised in this study can be used as reference materials for validation and quality control purposes and to estimate measurement uncertainties in conventional 87Sr/86Sr isotope ratio measurement.

This study uses conventional 87Sr/87Sr and 87Nd/87Nd isotope and interelement ratios of Ca, Sr, K, Mn, Mg, and Ti as fingerprints for ordinary Portland cements (OPC) provenancing. Herein, the first database of Sr and Nd isotope ratios investigated in OPCs stemming from twenty-nine cement plants located worldwide was created. The results show that the Sr isotope ratios of OPCs are higher than those of seawater from the observed geological period. The spread of 87Nd/87Nd in OPCs is not as large as the spread for 87Sr/87Sr isotope ratios. However, the combination of both Sr and Nd isotope ratios provides the potential for distinguishing between cements of different production sites. Most of the investigated OPCs have measurable differences in their 87Sr/87Sr and 87Nd/87Nd isotope ratios, which can be employed as a valuable analytical fingerprinting tool. In the case of equivocal results, Divisive Hierarchical Clustering was employed to help overcome this issue. The construction of geochemical profiles allowed computing suitably defined distances between cements and clustering them according to their chemical similarity. By applying this methodology, successful fingerprinting was achieved in 27 out of 29 analysed ordinary Portland cements.

The use of elemental analyses and isotope techniques for cement provenancing are reviewed. Based on the currently available data and approaches from related fields, future perspectives and a combined approach for cement provenancing are outlined.

Department of Chemistry, Faculty of Science, University of Sarajevo, Zmaja od Bosne 33–35, 71000 Sarajevo, Bosnia and Herzegovina Department of Biology, Faculty of Science, University of Sarajevo, Zmaja od Bosne 33–35, 71000 Sarajevo, Bosnia and Herzegovina Faculty of Metallurgy and Technology, University of Montenegro, Džordža Vašingtona bb, Podgorica, Montenegro University "Vitez", Vitez, Bosnia and Herzegovina

Oxidation of sulfide-containing ores is the main cause of Acid Mine Drainage (AMD), which is an environmental problem associated with both the abandoned and active mines. Iron-bearing sulfide minerals can be oxidized and form mine waters with high sulfate content, low pH, high electrical conductivity, high redox potential, and high concentrations of iron, aluminum, and other heavy metals. In the process of AMD, precipitation of poorly crystalized oxy-hydroxides of iron with a large active surface can occur. On the surface of iron oxy-hydroxide, the precipitated particulate matter, anions, and cations (metals) could be adsorbed. Mine waters can contain a certain amount of precious metals that can also be adsorbed onto an iron particulate matter surface, which is investigated in this research work. In this work, the samples of iron oxy-hydroxide particulate matter at abandoned gold mine waste in Bakovici (Central Bosnia and Herzegovina) are used. Several parameters including pH, water content, particle size distribution, sulfate content, electrical conductivity, redox potential, and amounts of gold, silver, and iron are measured on the selected mine waste samples. The results obtained indicate that significant amounts of gold (average: 6.8 mg/kg) and silver (average: 7.13 mg/kg) are present in the iron precipitate. Adsorption of precious metals onto the iron oxy-hydroxide surface is strongly pH-dependent. At a very low pH value, desorption of precious metals is favorite. Thus, precious metals are only partially adsorbed onto the iron oxy-hydroxide surface.