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Copyright of Transfusiology & Haematology Today / Transfuze a Hematologie Dnes is the property of Czech Medical Association of JE Purkyne and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Samples representing two modifications of halloysites, dehydrated (7 Å) and hydrated (10 Å) forms, respectively, were examined with the aim to select suitable candidates for to be used as carriers of porphyrine photoactive molecules. The samples were analysed by powder X-ray diffraction (pXRD), infrared spectroscopy (FT-IR), and high resolution transmission electron microscopy (HRTEM). Chemical composition was also determined. For the determination of cationic exchange capacity (CEC) the silver thiourea method (AgTU) was used. Silver cations concentrations in the solution before and after the interaction were determined by atomic absorption spectrometry (AAS). By the interaction of two pure hydrated halloysites with porphyrine it was found that porphyrine does not intercalate the interlayer space, but it is adsorbed on the outer surface of halloysite. This interaction changed the colour of clay sample from white to green. The changes were also clearly visible on diffuse reflectance spectra (DRS).

Vivianite (Fe3(PO4)2·8H2O) is a rare blue historical pigment, which can be profitably used in authorship ascription or copy identification. However, its tendency to degrade complicates its proper identification in paint layers. Reference vivianite mineralogical samples were analysed in order to compare and to test the limits of structural analyses on possibly degraded vivianite samples (X‐ray diffraction and vibrational spectroscopies). The same methods, in their μ‐configuration, were tested on micro‐samples of the paintings and their limits evaluated. A sedimentary origin of the pigment has been suggested. Vivianite was detected in various works by Jean George de Hamilton (1672–1737) and in a Late Gothic Transylvanian altarpiece. [ABSTRACT FROM AUTHOR]

Pre-Romanesque murals at Kostoľany pod Tríbečom, Slovakia, have been investigated by portable X-ray fluorescence and by microanalytical methods to identify painting materials (pigments and binders), and to explain the degradation of colours. Today, missing green and blue shades have been reconstructed according to residual concentrations of Cu, which correspond to copper chlorides-products of salt corrosion of the copper carbonates azurite and/or malachite, accelerated by micro-organisms. As confirmed by powder X-ray microdiffraction, original minium (Pb3O4) has been transformed to brown-black plattnerite (PbO2). In increased humidity, even insoluble pigments are washing down from the walls and the intensity of colours further diminishes. [ABSTRACT FROM AUTHOR]

Single-crystals of the layered copper hydroxide acetate Cu2(OH)3(CH3COO)·H2O were synthesized by heating copper acetate solution at 60 °C. The standard synthesis of the title compound based on slow titration of copper acetate solution with NaOH yielded materials with worse morphology and an additional phase present. The obtained products were characterized with powder X-ray diffraction, high temperature powder X-ray diffraction, scanning electron microscopy and infrared spectroscopy. The crystal structure was determined from single-crystal X-ray diffraction data, collected both at 120 K and at 293 K. The title compound crystallizes in the monoclinic botallackite-type layered structure, space group P 21, with the lattice parameters a = 5.5776(3) Å, b = 6.0733(2) Å, c = 18.5134(8) Å, β = 91.802(4)° and a = 5.5875(4)Å, b = 6.0987(4) Å, c = 18.6801(10)Å, β = 91.934(5)° for 120 K and for 293 K, respectively. Acetate groups and water molecules are interlayered between corrugated sheets of edge-sharing CuO6 octahedra exhibiting strong distortion resulted from the Jahn-Teller effect. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

While the most famous historical green earth deposits in Italy and Cyprus were exceptionally rich in celadonite, the deposits near Kadaň, Czech Republic, consisted of thin Fe-rich celadonite impregnations accompanied by interstratified celadonite/smectite. In superimposed tuffs, smectites become prevalent and their colour changes from forest to olive green. Powder X-ray microdiffraction and infrared microspectroscopy permit us to distinguish between green earth minerals in microsamples taken from works of art. The Ti contents and the Fe/Mg ratios help to indicate the presence of Bohemian green earth from Kadaň. We found this material in local 18th-century works of art and also in paintings by Anton Kern (1709-47). [ABSTRACT FROM AUTHOR]

Azurite, a historical blue mineral pigment, has previously been described to contain certain elemental impurities. These may originate from host rocks, vein fillings, or the primary copper ore mineralization. In this study, azurites (and also green malachites) from three important Central European deposits with a potential of being exploited for pigment usage already in the Middle Ages have been studied, together with azurite from Chessy, France, with a different geological setting. Using electron probe microanalysis and, more importantly, laser ablation inductively coupled plasma mass spectroscopy for trace elemental analysis, several indicators were pinpointed as important for provenance: characteristic elemental fingerprint of the deposit, e.g., elevated lead (Pb) in combination with rare earth elements, may be combined with zinc (Zn)/arsenic (As) ratio (indicating sources of excess Zn in the primary deposit) and the overall amount of metal impurities (suggesting the source mineral of copper for azurite formation). In addition, malachites from the same deposits were found to preferentially incorporate primary ore metal elements as well as Cd, Mg, Mn, or U. Therefore, if azurite pigment contains an elevated amount of malachite as an impurity, it may significantly influence the overall elemental composition. The results obtained on geological samples were applied to two micro-samples of works of art containing azurite-rich layers originating from the 13th-14th and 16th centuries. It was shown that it is highly beneficial to focus on the overall trace elemental composition of the paint layer and not on the admixed mineral grains, as their presence, especially in minute micro-samples, is largely accidental and thus not representative. Although a higher number of samples need to be studied in the future, the newly described criteria made it possible to exclude some of the localities of the employed azurite pigment. This confirmed the key importance of trace elements analysis of mineral pigments for the provenance studies of fine arts., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

While the natron and plant ash glass tesserae may be found on places of importance across the former Roman and Byzantine empires, wood ash glass tesserae are scarce. This is the first time a wood ash glass tessera is studied in detail. It was part of a magnificent 8-metres tall statue of Madonna in Malbork, Poland, created at the end of the 14th century and destroyed at the end of World War Two. It was found to be coloured by cobalt with possible impact of copper, and opacified by Ca-phosphate. Processes previously described in sodium-rich glasses were observed also in the studied potassium-rich wood ash glass tessera, such as diffusion of the respective alkali metal into the Ca-phosphate grains. The elemental composition of the tessera indicates that it is original - mediaeval, from the area north of Alps. Two phases were identified for the first time, to authors' best knowledge, in any glass tessera - leucite (tetragonal KAlSi 2 O 6 ) and pseudowollastonite (monoclinic CaSiO 3 ). As pseudowollastonite is a high-temperature phase, it may serve as an indicator of production temperature, which was further supported by the study of polymerisation index of model glasses. This study contributes to the knowledge of old technologies and showed that the know-how for opacification was imported from the Mediterranean, while the raw materials employed for the base glass preparation were from the area north of Alps., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Many issues in the conservation of paintings from the early modern period are still unresolved due to lack of information on paints from the late 19th and early 20th centuries, in particular their production, formulations, and later degradation processes. The inconsistency of the names that paint manufacturers chose for their products furthermore compounds the challenges faced by conservators and chemists wishing to study them. This paper addresses a number of these issues through investigations of commercial tube oil paints from a paint box owned by the Norwegian painter Harriet Backer (1845-1932). Samples were analyzed using a multi-instrumental approach. Micro-attenuated total reflection Fourier transform infrared spectroscopy and micro-Raman spectroscopy - supported by micro-X-ray powder diffraction - allowed the identification of binders, pigments, and extenders. The data highlight the use of materials that were new at the time and not reported in the manufacturer's catalog. Furthermore, zinc stearate has been detected for the first time. Its detection and the absence of any zinc-based pigments confirms that zinc stearate was already used as dispersing agent in paint formulations at that time., (Copyright © 2022 Elsevier B.V. All rights reserved.)