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Organic chromophores have been successfully implemented into supramolecular systems to bestow them with distinct photophysical properties for various applications, ranging from solar energy conversion, photochemical reactions or as receptors for guest molecules with optical readout. We had previously introduced first members of the large family of coal‐tar dyes (methylene blue, crystal violet and rhodamine) as integral components of coordination cages. Here, we add two new chromophores, malachite green (MGP) and a purple phenazinium dye (PHP), serving as backbones of bis‐monodentate banana‐shaped ligands with pyridine donors. We show the formation of corresponding green and purple coloured Pd2L4 coordination cages and investigate their interaction with chiral guest molecules via UV‐Vis and CD spectroscopy. The PHP cage can be used to recognize nucleoside triphosphates, based on chirality transfer from the guests to the structurally flexible helicate. In combination with the already known methylene blue cage MBP we could further differentiate between all four canonical NTPs through characteristic changes in the observed CD signatures. [ABSTRACT FROM AUTHOR]

Photo-responsive malachite green moieties have been incorporated into an alkynylplatinum(II) bzimpy system. The photo-caged complexes in acetonitrile solutions exhibit self-assembly properties modulable by photo-removal of the cyano protecting group. Distinct aggregate morphologies, which are facilitated by the non-covalent metal–metal and π–π stacking interactions, have been observed before and after photo-irradiation. [ABSTRACT FROM AUTHOR]

Malachite is a common copper oxide mineral that is often enriched using the sulfidization–xanthate flotation method. Currently, the direct sulfidization method cannot yield copper concentrate products. Therefore, a new sulfidization flotation process was developed to promote the efficient recovery of malachite. In this study, Cu2+ was used as an activator to interact with the sample surface and increase its reaction sites, thereby strengthening the mineral sulfidization process and reactivity. Compared to single copper ion activation, the flotation effect of malachite significantly increased after stepwise Cu2+ activation. Zeta potential, X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectroscopy (ToF–SIMS), scanning electron microscopy and energy dispersive spectrometry (SEM–EDS), and atomic force microscopy (AFM) analysis results indicated that the adsorption of S species was significantly enhanced on the mineral surface due to the increase in active Cu sites after Cu2+ stepwise activation. Meanwhile, the proportion of active Cu–S species also increased, further improving the reaction between the sample surface and subsequent collectors. Fourier-transform infrared spectroscopy (FT-IR) and contact angle tests implied that the xanthate species were easily and stably adsorbed onto the mineral surface after Cu2+ stepwise activation, thereby improving the hydrophobicity of the mineral surface. Therefore, the copper sites on the malachite surface after Cu2+ stepwise activation promote the reactivity of the mineral surface and enhance sulfidization flotation of malachite. [ABSTRACT FROM AUTHOR]

Five historical green dyes from the Historische Farbstoffsammlung, Technical University of Dresden, have been analysed by liquid chromatography – mass spectrometry (LC-MS). The dyes were determined to be formed by the alkylation of either crystal violet or rosaniline and contained both doubly and singly charged ions. One sample had a spread of higher molecular weight doubly charged ions reminiscent of the alkylation of a Hofmann violet. Malachite green was the dye present in one sample. [ABSTRACT FROM AUTHOR]

In this study, the dissolution conditions and dissolution kinetics of copper from malachite in the presence of organic acid (C4H6O6) as an organic leaching reagent were examined. The effects of particle size, acid concentration, time, solid/liquid ratio, temperature, and mixing speed on the dissolution process of copper were investigated. According to the test results, optimum dissolution conditions are as follows: particle size was 74 µm; organic acid concentration was 0.2 mol/L; duration was 60 min; solid/liquid ratio was 1/10; the temperature was determined as 25 °C and the stirring speed was 300 rpm; and the copper extraction value was obtained as 73.18% under optimum experimental conditions. Kinetic models were applied to the dissolution efficiencies obtained to determine the dissolution kinetics of copper in the presence of organic acid, and it was found that the dissolution process was controlled by the film diffusion model. In light of the data obtained, it can be said that organic acid, which is an economical and environmentally friendly leaching reagent, can be used in the dissolution of copper from malachite (Cu (OH) 2 CuCO 3) , as well as in the leaching of other precious metals such as copper, zinc, and cobalt from oxide and carbonate ores. [ABSTRACT FROM AUTHOR]

This study measured the infrared spectra of secondary minerals in the oxidation zones of three types of copper ores: dioptase, malachite, and azurite, and assigned the peak positions of OH stretching vibrations and the origins of OH combination vibrations. Dioptase contains three types of water molecules with different orientations within its ring channels, which exhibit six kinds of OH stretching vibrations in the 3000–3600 cm−1 range; the bond length range is 2.652 to 2.887 Å. Among them, the 3443 cm−1 band shows strong near-infrared activity and combines with Si–O vibrations or OH bending vibrations in the structure, resulting in five combination vibration peaks in the 4000–5000 cm−1 range. Malachite contains two inequivalent hydroxyls in its structure, leading to two OH stretching vibrations in the high-frequency region located at 3314 and 3402 cm−1, respectively. Azurite contains only one type of hydroxyl, and thus only one characteristic OH stretching vibration is present at 3424 cm−1. The OH stretching vibrations of malachite and azurite mainly combine with [CO3]2− vibrations or OH bending vibrations, leading to six and five combination peaks in the OH combination vibration region, respectively. By analyzing the combination of peak positions at 4341 cm−1 in the near-infrared spectrum, the merged OH bending vibration at 921 cm−1 in azurite was discovered. Spectroscopic research on secondary minerals can better provide a basis for ore exploration and geological remote sensing. [ABSTRACT FROM AUTHOR]

Manto-type copper mines occur in the Bardaskan-Doruneh copper belt. On the basis of structural sedimentary division of Iran, this belt is located in the northeastern part of the Central Iran. At the southern border of this belt, the Yazd structural block and in the north of it is the Sabzevar subzone. The important regional structures of the region are Doruneh and Taknar faults. The majority of the units in this belt are Tertiary volcanic rocks that is associated with some sedimentary units, also some intrusive units are sometimes visible in the form of dyke and stock structures. The main host-rock of mineralization is conglomerate, which is different in grain size, clasts and cement. The most common sulphide mineral is chalcocite and the most important copper carbonates are malachite and azurite. The intense alteration is not observed in the region, and the chloritic alteration is partial, and the alteration of Fe-Oxide, zeolite, calcite, and silica is just observed locally. Mineral solution is reduced and poor in iron and silica. Introduction Manto type copper deposits in the Bardaskan-Doruneh copper belt, with a length of approximately 60 km in a northeast-southwest direction, host more than ten active copper mines such as Zangalu, Zarmehr, Dahane-Siah, Mehr-Ajin, Mes-e-Sorh, Cheshme Hadi, Nasim, Sepidsarw, Cheshme Marzieh and a number of mineral areas, which according to the characteristics of these types of deposits (location, genetic pattern, geometry, host rock, minerals, etc.) and their similarities with Manto type copper deposits in Chile, Canada and the northern Michigan area, it is called as Manto-copper deposits in Iran. Materials and Methods This research includes two parts of field and laboratory investigations. Field studies were carried out in a region with about 60 km in length. Field operations include surveying and searching the area, sampling and distinguishing rock units and mineralization indicators, as well as important geological features of the area. The number of 20 thin sections for lithological investigations, as well as 20 polished thin sections and 10 blocks of drill cores (examination and study of 20,000 meters of drill core related to Nasim, Zarmehr, Mes-e- Sorkh, Cheshme Hadi and Kimia mines) and surface outcrops for a map of mineralization in the area was prepared and studied. Field surveys were conducted for mineralization controllers and host rock changes in the mining pits of Nasim, Zarmehr, Mes-e-Sorkh and Cheshme Hadi mines. Also, due to the importance of tectonic structures, a structural map of the mines was prepared. Discussion and Results The rock units from old to young include: Basalt, Andesite-Basalt, Andesite, Conglomerate with more volcanic fragments, Limestone, Siltstone, Marl and evaporite sediments including gypsum Marl. The general extension of this lithological sequence is northeast-southwest. Mineralization has occurred within the conglomerate unit. There are different types of conglomerate based on the size of the clasts, the lithology of the clasts, and the cement. The type of conglomerate has a great effect on mineralization and grade changes. Conglomerate is a suitable host for mineralization due to the porosity of the rock. The dip and strike of the ore body follows the dip and strike of the lithological units of the region and the deposit is of the stratibound type. Mineralization zone has a variable thickness between 2 and 6 meters (in some places, the thickness increases due to the action of faults). The dip of the ore body varies in different parts and is between 15 and 80 degrees towards the south and southeast. The mineralization texture is mostly disseminated and veined and is mainly as chalcocite mineral. In some places, due to effect of tectonic forces and the formation of fault structures, the order and sequence of units has been dislocated and messed up. Fault structures: The first group of fault structures with the northeast-east to southwest-west direction are the most important fault structures. These fault structures form the boundary between the Andesite unit and the sedimentary units and in the surface of mineralization outcrop can be seen along its length and it is one of the old structures in the region because it has been cut and dislocated many times by other fault structures. The second group is the north-south oriented structures and caused displacements in the mineralized host unit. This fault system, which itself consists of several parallel fault structures, has caused the creation of secondary spaces and the intensification of mineralization, and as a result, the grade has increased in some parts of the region by joining these parallel faults together and with deepening of the basin the intensity of mineralization has increased. The third group of fault structures with the northwest-southeast direction are right lateral strike-slip and minor left lateral strike-slip faults. These structures are one of the most important fault structures in the region, which displaced the rock units of the region, especially the host of mineralization.

Transition metal complexes have historically played a pivotal role in creating vibrant pigments utilized across artistic mediums such as ceramics, paintings, and glass mosaics. Despite their extensive historical use, our understanding of the mechanisms governing transition metal complex behavior has predominantly emerged in recent times, leaving numerous aspects of this process ripe for exploration. These complexes exhibit striking color variations under diverse conditions when employed in pigment formulations. This review utilizes a bottom-up scientific approach, spanning from microscopic to macroscopic scales, to unravel the molecular origins of the colors generated by transition metal complexes in pigments and ceramic glazes. Advanced spectroscopy techniques and computational chemistry play pivotal roles in this endeavor, highlighting the significance of understanding and utilizing analytical data effectively, with careful consideration of each technique’s specific application. Furthermore, this review investigates the influence of processing conditions on color variations, providing valuable insights for artists and manufacturers aiming to enhance the precision and quality of their creations while mitigating environmental impact.

The Imourkhssen porphyry Cu±Mo±Au±Ag deposit is located at the Ouzellagh-Siroua Salient (OSS) straddling the boundary between the central Anti-Atlas and the central High Atlas. It is characterized by a typical porphyry-style mineralization. The volcanic rocks are intruded by numerous magmatic rocks of the Ouarzazate Group (580–539 Ma), referred to as the Late Ediacaran magmatic suites (LEMS). Of these, the Askaoun, Imourkhssen, and Imourgane granites are the most significant as they are related to the porphyry mineralization. The entire set is intruded by the Zaghar mafic dyke swarms. Zircon U-Pb dating of the Imourkhssen granite and the ore-bearing granite porphyry shows that these intrusive rocks were emplaced at 558 ± 1 and 550 ± 2 Ma, respectively. Moreover, the whole-rock major and trace element geochemistry reveal a high-K calc-alkaline I-type composition, consistent with an emplacement in a post-collisional setting under a trans-tensional tectonic regime. Ore bodies are hosted by the Askaoun granodiorite as well as the Imourgane granite. The mineralization occurs as fine-grained dissemination and infills of hydrothermally altered NNE–SSW to N–S trending veins and veinlets. Ore-related hydrothermal alteration consists of potassic, chlorite-sericite, serecitic, and propylitic mineral assemblages along with pervasive silicification and pyritization, providing a porphyry-style alteration pattern. The ore periods comprise supergene and magmatic-hydrothermal periods. The latter includes primary dissemination and secondary NNE–SSW to N–S ore-bearing system stages. The occurrence of molybdenite is either restricted to the potassic and chlorite-sericite alteration zones of the ore-bearing granite as fine disseminations or alternatively as veinlet infills within the propylitic halos. The molybdenite occurrences along with pyrite, chalcopyrite, galena, and tennantite dissemination are assigned to the primary ore stage, while the NNE–SSW to N–S ore-bearing system is related to the secondary ore stage. It consists of pyrite, chalcopyrite, bornite, covellite, diagenite, sphalerite, hematite, galena, gold, and chenguodaite. The predominance of cockade and crack-and-seal textures suggest multiple episodes of ore-forming fluid circulations under epithermal conditions. The supergene stage is achieved by subordinate malachite, azurite, barite, hematite, epsomite, and chrysocolla. From the descriptions above, we argue that the Imourkhssen Cu±Mo±Au±Ag mineralization shares many mineralogical and paragenetic attributes of porphyry-copper deposits. [ABSTRACT FROM AUTHOR]

The stratabound barite mineralization occurs in the Ardakan deposit as patches and veins in the dolomites and limestones of the Middle Triassic Shotori Formation. Rare-earth element (REE) geochemistry, O and S isotopes, and fluid inclusion data were used to identify the mode of barite formation. Barite is associated with subordinate fluorite and quartz and, to a lesser extent, with sphalerite, malachite, chrysocolla, and iron and manganese oxide-hydroxides. Barite contains a very low ∑REE concentration (14.80–19.59 ppm) and is enriched in light rare-earth elements (LREEs) relative to heavy rare-earth elements (HREEs). The low ∑REE content and the Ce/La ratio (4.0–6.5) indicate a hydrothermal (terrestrial) origin of the barite. Similar to barite, the ∑REE content in fluorite is low (0.14–6.52 ppm) and suggests a sedimentary setting. The Tb/Ca versus Tb/La diagram also indicates a hydrothermal origin of fluorite. The δ34S values in the barite (+27.9 to +32.4‰) indicate that the sulfur most likely originates from evaporites and/or connate waters from the Late Precambrian to the Lower Cambrian. The δ18O values (+15.9 to +18.1‰) in the barite show that the oxygen originated either from Late Precambrian–Lower Cambrian evaporites or from basinal brines with slightly higher δ18O values than the evaporites. The salinity and homogenization temperature ranges of the aqueous fluid inclusions in barite, fluorite, and quartz (0.88–16.89 wt% NaCl equivalent and 90–270 °C, respectively) reveal that the mineralizing fluids were formed from basinal brines with the participation of heated meteoric water. From this, it is concluded that the Ardakan barite deposit was formed by the meeting of heated, ascending sulfate-bearing meteoric water and cooler, Ba-bearing connate water trapped in the overlying Middle Triassic dolomites and limestones. The Ardakan deposit belongs to the structure-related class and the unconformity-related subclass of barite deposits. [ABSTRACT FROM AUTHOR]

Aging is one of the key steps in the preparation of highly active Cu/ZnO-based catalysts for use in the production of methanol. If certain pH and temperature specifications are met, an initially amorphous precipitate transforms into the crystalline precursor phase of zincian malachite, which is characterized by a periodic arrangement of Cu and Zn atoms and has proven advantageous for the quality of the final catalyst. However, aging generally takes between 30 min and multiple hours until the desired phase transformation is completed. With our study, we show that aging can be significantly accelerated by seeding the freshly precipitated suspension with already aged zincian malachite crystals: the necessary aging time was reduced by 41% for seeding mass fractions as low as 3 wt.% and from 83 min to less than 2 min for 30 wt.% seeds. No negative influence of seeding on the phase composition, specific surface area, molar metal ratios, or the morphology of the aged precursor could be identified. Consequently, the catalyst performance in the synthesis of methanol from CO2, as well as from a CO/CO2 mixture, was identical to a catalyst from an unseeded preparation and showed small advantages compared to a commercial sample. Thus, we conclude that seeding is a vital tool to accelerate the preparation of all Cu/Zn-based catalysts while maintaining product quality, presumably also on an industrial scale. [ABSTRACT FROM AUTHOR]

The supergene zone of the Cap Garonne mineral deposit (Provence, France) hosts one of the most remarkable mineralogy in the world with no less than 150 minerals, 16 of which are type locality. Such mineral diversity offers a detailed view of mineral and geochemical changes during weathering processes. The stratabound epigenetic primary mineralization occurs within a few meters-thick fluvial conglomerates resting above the Permian–Triassic transition and is probably related to Late Triassic–Early Jurassic hydrothermal events. The Cu–As mineralization in the lower part of the conglomerates is locally overlapped by a thin Pb–Zn-rich layer in the northern mine. The results show that the weathered part is significantly enriched in Cu, Pb, As, Zn, Ag, Ba, Sb, and Bi. The evolution of the supergene fluid is traced in an Eh–pH diagram by the succession of sulfides I (tennantite, galena), sulfides II (covellite), arsenates (olivenite), sulfates and sulfo-arsenates (brochantite, anglesite), and carbonates (malachite, azurite, cerussite). The primary sulfide oxidation acidified the host conglomerate and enabled the crystallization of secondary sulfides and arsenates. Efficient and rapid neutralization by the calcite cement of the host conglomerate and chlorite in the matrix caused successive precipitation of arsenates, sulfates, and carbonates. The supergene processes could be related to major periods of weathering in Western Europe (Early Cretaceous–Late Oligocene/Early Miocene). Erosion-prone periods may have contributed to the stripping of the Pb–Zn-rich layer in the southern mine. [ABSTRACT FROM AUTHOR]

Color aberrations in birds corresponds with important ecological functions, including thermoregulation and physiological impacts, camouflage and increased predation, and social interactions with conspecifics. Color aberrations in birds have been reported frequently in the scientific literature, but aberrations in many species remain undocumented or understudied. We investigated records of leucism in malachite kingfishers (Corythornis cristatus) from observations of community scientists on iNaturalist and eBird in Uganda. Leucistic kingfishers were only observed within the Queen Elizabeth National Park (QENP), Uganda. When considering all observations of malachite kingfishers that included photographs within the QENP, leucistic individuals accounted for 13.0% and 10.4% of total malachite kingfisher observations within the study area from iNaturalist and eBird, respectively. Leucistic observations were recorded from September 2015 through February 2017, making up 60.0% and 68.2% of observations of malachite kingfishers within the study area from iNaturalist and eBird during that time, respectively. The localized and short documentation period suggests observations represent a single individual, while the high observation rate likely corresponds with collection bias due to the novelty of the individual. Our findings help to better understand the ecological importance and potential consequences for color‐aberrant individuals, although color aberration did not appear to inhibit our subject's ability to find a mate. Our work also highlights how participatory science can promote the documentation of color‐aberrant individuals in wild populations, although it poses challenges when trying to estimate abundance. [ABSTRACT FROM AUTHOR]

In this study, copper wares excavated from tombs in the Qinghai Province of China were investigated. Using varied analysis methods, this study analyzes the layered corrosion products of copper ware. Furthermore, it discusses the relevant corrosion mechanism along with the burial environment, condition, and manufacturing craft. The forged copper wares appear to be in a state of stratified corrosion in the burial environment. Beginning from the outside and moving toward the inside, the following layers were observed: malachite and azurite; atacamite and clinoatacamite; cuprite and clinoatacamite; and the innermost layer, which is a residual metal layer in some regions. In the cuprite layer, the presence of clinoatacamite was observed to destroy the structure of the cuprite and form fine stratification, which, in turn, promoted the further development of chlorine-containing corrosion products and led to the 'peeling off' of copper ware. This study explores the destructive corrosion caused by Cl in copper ware. [ABSTRACT FROM AUTHOR]

The relationship between the structure of bis (2,4,4-trimethylpentyl) phosphinic acid (BTPA), diethyl phosphinic acid (DEPA), and diphenyl phosphinic acid (DPPA) on the flotation performance of malachite was investigated. Through a series of flotation experiments, density functional theory (DFT) calculations, and surface analysis methods, we aimed to deeply understand the microscopic mechanism of the interactions between these collectors and the malachite surface. The experimental results showed that BTPA exhibited excellent selectivity and flotation performance for malachite in the pH range of 5.0–11.0, significantly better than DEPA and DPPA. Surface analysis evidence from X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR) further confirmed the chemical adsorption characteristics of BTPA on the malachite surface. DFT calculations revealed that the adsorption capacity of BTPA on the malachite surface exceeds that of DEPA and DPPA. Electron transfer analysis, especially through frontier molecular orbital theory, differential charge density, PDOS, and COHP analysis, indicated that the charge transfer process from the s orbitals of oxygen atoms in the collectors to the d orbitals of copper atoms on the mineral surface is the decisive factor for the adsorption strength. [ABSTRACT FROM AUTHOR]

Transition metal complexes have historically played a pivotal role in creating vibrant pigments utilized across artistic mediums such as ceramics, paintings, and glass mosaics. Despite their extensive historical use, our understanding of the mechanisms governing transition metal complex behavior has predominantly emerged in recent times, leaving numerous aspects of this process ripe for exploration. These complexes exhibit striking color variations under diverse conditions when employed in pigment formulations. This review utilizes a bottom-up scientific approach, spanning from microscopic to macroscopic scales, to unravel the molecular origins of the colors generated by transition metal complexes in pigments and ceramic glazes. Advanced spectroscopy techniques and computational chemistry play pivotal roles in this endeavor, highlighting the significance of understanding and utilizing analytical data effectively, with careful consideration of each technique's specific application. Furthermore, this review investigates the influence of processing conditions on color variations, providing valuable insights for artists and manufacturers aiming to enhance the precision and quality of their creations while mitigating environmental impact. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive analysis of three bronze ring fragments with distinct corrosion patterns from the Nanhai No.1 shipwreck, employing optical microscopy, SEM–EDS, µ-RS, and µ-EDXRF techniques. The results exhibit that each bronze ring fragment displays unique corrosion characteristics but shares similarities in their patina structures: an outer layer composed of CuFeS2) and malachite, a subsurface layer of CuS) and/or Copper Tin Sulfide, and an inner copper-depleted layer rich in tin and lead. These layers indicate the artifacts experienced three distinct corrosion stages corresponding to aerobic, anaerobic, and re-aerobic conditions, aligned with the ship's sinking, sediment coverage, and post-recovery scenarios. The study reveals that the pre-anaerobic corrosion products significantly influenced the corrosion kinetics in subsequent environments, affecting the final composition and structure of the patina. Notably, the outer CuS layer, regardless of its compactness, is unable to prevent the selective dissolution of copper from the alloy. The formation of a cuprite layer beneath the copper-depleted layer post-recovery suggests a corrosion resumption due to changes in environmental oxygen levels. These insights emphasize the need for targeted conservation strategies for marine-recovered bronze artifacts, considering their complex corrosion history and environmental interactions. [ABSTRACT FROM AUTHOR]

Improving the recovery of fine copper oxides is an important problem to be solved in the efficient utilization of copper ore resources. It is of great significance to study the selective flocculation separation of fine malachite and quartz for efficient recovery of copper ore resources. Using xanthan gum as flocculant, the selective flocculation and settlement behavior of malachite and quartz were studied. The results show that when pH value is 4, xanthan gum concentration is 10 mg/L, Cu2+ concentration is 20 mg/L, the recovery of single mineral malachite is 91.81%, the difference of settlement rate between the two minerals is 64.73 percentage points, the settlement rate of the minerals mixture is 66.61%, the recovery malachite is 72.44% and the Cu grade is 30.18%. The results of microscope observation show that the adsorption capacity of xanthan gum for malachite is stronger than that of quartz. Xanthan gum can selectively flocculate fine malachite particles and agglomerate them into large size of particle floes, which is conducive to settlement. The determination of adsorption capacity and Zeta potential analysis showed that xanthan gum had electrostatic interaction with malachite and physical adsorption with quartz, and Cu2+ would have electrostatic interaction with xanthan gum covered on the surface of quartz, but had little effect with quartz; The results of FTIR test show that xanthan gum can be adsorbed on malachite surface for chemical reaction. When Cu2+ and xanthan gum are added, there is hydrogen bond between xanthan gum and malachite, and xanthan gum can also form stable complex of Cu2+. The interaction between xanthan gum and quartz is mainly physical adsorption. XPS test results showed that xanthan gum adsorbed Cu2+ on malachite surface, bonded to Cu site on malachite surface, and obtained electrons from malachite -OH and C = O groups. The adsorption between xanthan gum and quartz is weak. Xanthan gum can effectively separate malachite from quartz, improve the grade of malachite product. This study provides theoretical guidance for the recovery and utilization of fine malachite. [ABSTRACT FROM AUTHOR]

Abstract We present a study into early modern English production of blue verditer, an early synthetic copper-based blue pigment chemically analogous to azurite. Verditers have been identified in numerous wall and easel paintings. While initial documentation occurs in the mid 1500s and production recipes were documented by the 17th c., the synthesis was known to be unreliable. This study replicates historical and recent scientific work on blue verditer and represents a significant advance in our understanding of verditer production and its challenges. Procedures for verditer synthesis are drawn from both 17th c. documentation and 20th c. replication work. The effects of temperature, copper and carbonate sources, solution stirring, copper ion concentration, and atmospheric composition are studied in order to elucidate the mechanism of synthesis and explain its unreliability in early modern refineries. Products are characterised by polarised light microscopy, scanning electron microscopy, Raman spectroscopy, and powder X-Ray diffraction. Rouaite, a green basic copper nitrate, is for the first time confirmed as a product of the refiners’ synthesis and a precursor to blue verditer in laboratory syntheses. This result problematises the blanket identification of green verditer as basic copper carbonate and provides important clues to the mechanism for blue verditer synthesis. Solution chemistry and ion equilibria allow us to explain the route by which rouaite is first formed and then converted to blue verditer. Conditions favouring blue verditer production are also clarified further. Although it is commonly stated that low temperatures are required for blue verditer production, blue verditer is produced here at a range of ambient temperatures. The reaction is found instead to be controlled by solution equilibria and heavily favoured by high partial pressures of carbon dioxide. Alongside archival materials about refining and verditer production, these results are contextualised and explanations for the unreliability of historical synthesis are proposed.

Malachite is one of the most important copper-bearing oxide minerals; however, it shows poor floatability prior to sulfidization under the thiol collector system. This study investigated the reasons for the low recovery of malachite flotation without sulfidization. The results of adsorption capacity and contact angle test indicated that the malachite surface could adsorb a sufficient amount of the collector, obviously increasing the hydrophobicity of the malachite surface under static conditions. By measuring the amount of inorganic carbon in the flotation solution, it was found that the amount of inorganic carbon in the solution increased significantly when the thiol collectors were added into pulp, which could be attributed to the induced dissolution of the malachite surface by thiol collectors. Solubility tests further demonstrated that the copper ions released from the natural dissolution of malachite proved difficult in regard to reactions with thiol collector to form precipitates; however, the thiol collector induced the dissolution of malachite surface, and so the hydrophobic complexes' copper-collector could not firmly adsorb on the mineral surface. Fourier transform infrared (FTIR) analysis revealed that thiol collectors do not adsorb stably on malachite surfaces. This was considered to be a substantial reason for the poor performance of malachite flotation without sulfidization. [ABSTRACT FROM AUTHOR]

We present a study into early modern English production of blue verditer, an early synthetic copper-based blue pigment chemically analogous to azurite. Verditers have been identified in numerous wall and easel paintings. While initial documentation occurs in the mid 1500s and production recipes were documented by the 17th c., the synthesis was known to be unreliable. This study replicates historical and recent scientific work on blue verditer and represents a significant advance in our understanding of verditer production and its challenges. Procedures for verditer synthesis are drawn from both 17th c. documentation and 20th c. replication work. The effects of temperature, copper and carbonate sources, solution stirring, copper ion concentration, and atmospheric composition are studied in order to elucidate the mechanism of synthesis and explain its unreliability in early modern refineries. Products are characterised by polarised light microscopy, scanning electron microscopy, Raman spectroscopy, and powder X-Ray diffraction. Rouaite, a green basic copper nitrate, is for the first time confirmed as a product of the refiners' synthesis and a precursor to blue verditer in laboratory syntheses. This result problematises the blanket identification of green verditer as basic copper carbonate and provides important clues to the mechanism for blue verditer synthesis. Solution chemistry and ion equilibria allow us to explain the route by which rouaite is first formed and then converted to blue verditer. Conditions favouring blue verditer production are also clarified further. Although it is commonly stated that low temperatures are required for blue verditer production, blue verditer is produced here at a range of ambient temperatures. The reaction is found instead to be controlled by solution equilibria and heavily favoured by high partial pressures of carbon dioxide. Alongside archival materials about refining and verditer production, these results are contextualised and explanations for the unreliability of historical synthesis are proposed. [ABSTRACT FROM AUTHOR]

The Mahour base metal deposit is located northeast of Badroud in the middle of the Urumieh–Dokhtar magmatic arc in the Isfahan province of Iran. The main host rocks to the ores are Eocene volcanic and volcaniclastic rocks. Hypogene ore minerals constituting the main ore body are galena, sphalerite, pyrite, and chalcopyrite. In addition to gangue quartz, a variety of supergene minerals comprising gypsum, goethite, hematite, "limonite", malachite, azurite, covellite, and chalcocite are also present; gangue minerals are quartz, barite, calcite, sericite, and chlorite. Silicification, intermediate argillic, and propylitic are the main wall-rock alteration types. The presence of fluid inclusions with different vapor/liquid ratios in quartz and sphalerite could indicate a boiling process. The primary liquid-rich fluid inclusions suggest that the homogenization temperature was between 107 and 298 °C from fluids with salinities from 1.5 to 13.7 wt.% NaCl equiv. These data suggest that the ore-forming fluids were magmatic with a contribution from meteoric waters. The δ34S values of sulfides range from 1.9 to 3.4‰, those of barite range from 12.1 to 13.2‰, and those of gypsum range from 4.3 to 5.6‰. These data suggest that sulfur was mostly of magmatic origin with a minor contribution from sedimentary rocks. Our data suggest that the boiling of fluids formed an intermediate-sulfidation style of epithermal mineralization for the Mahour deposit. [ABSTRACT FROM AUTHOR]

In this paper, aurichalcite was synthesized by ammonia distillation method, using basic copper carbonate, basic zinc carbonate and concentrated ammonia as raw materials. The effects of process conditions on the crystal structure of aurichalcite were studied by XRD, TGA, SEM-Mapping and FT-IR. It is demonstrated that when the copper concentration is fixed at 120 g/L, and the molar ratios of copper to zinc are set at 3:2, 1:1 and 2:3, respectively, the crystals in the precipitation product consist of aurichalcite and malachite. As the molar ratio of copper to zinc decrease, the number of malachite crystals decrease. When the molar ratio of copper to zinc is 2:3, a further reduction in the number of malachite crystals is observed when the copper concentration reduce from 120 g/L to 80 g/L. Finally, under the condition that the molar ratio of copper to zinc is 2:3 and the copper concentration is 80 g/L, single-phase aurichalcite crystals are precipitated. This provides basic data for controlling the synthesis of aurichalcite by ammonia distillation method. [ABSTRACT FROM AUTHOR]

Painted artefacts, such as murals and paintings, are the treasures of human civilization. Pigment is an important component of their surfaces. It is crucial to study the composition and proportion of pigments on the surface of painted artefacts for the field of heritage conservation. In this study, hyperspectral remote sensing was used to invert the abundance of mixed pigments by spectral unmixing. Spectral variability effects are often present in hyperspectral images. Hyperspectral images of cultural artefacts also suffer from spectral variability due to factors such as particle size and impurities within the pigment, and acquisition conditions. Therefore, spectral variability was incorporated into the Linear Mixed Model of the pigment spectral unmixing. The unmixing methods are classified into two categories based on whether or not spectral libraries are used. In the experiment, computer synthesized data and laboratory-made sample blocks of mixed pigments, which mixed with different ratios of Azurite and Malachite, were selected as validation data. Five commonly used algorithms for solving the spectral variability problem, namely MESMA, Fractional Sparse SU, ELMM, RUSAL, and BCM, are used for pigment unmixing and compared with FCLS, which does not consider spectral variability. The results show that ELMM has the highest unmixing accuracy of aRMSE and xRMSE compared to other methods. At the same time, it can be seen from the metric of SAM that ELMM is able to extract reliable endmember variability spectral, which is more suitable for solving the problem of spectral variability in pigment unmixing. Finally, we apply ELMM to real artefacts Yungang Grottoes mural paintings, and obtain a lower xRMSE than FCLS, which improves the unmixing accuracy. [ABSTRACT FROM AUTHOR]

Manto-type copfa mines occur in the Bardaskan-Doruneh copfa belt. On the basis of structural sedimentary division of Iran, this belt is located in the northeastern part of the Central Iran. At the southern border of this belt, the Yazd structural block and in the north of it is the Sabzevar subzone. The important regional structures of the region are Doruneh and Taknar faults. The majority of the units in this belt are Tertiary volcanic rocks that is associated with some sedimentary units, also some intrusive units are sometimes visible in the form of dyke and stock structures. The main host-rock of mineralization is conglomerate, which is different in grain size, clasts and cement. The most common sulphide mineral is chalcocite and the most important copfa carbonates are malachite and azurite. The intense alteration is not observed in the region, and the chloritic alteration is partial, and the alteration of Fe-Oxide, zeolite, calcite, and silica is just observed locally. Mineral solution is reduced and poor in iron and silica. IntroductionManto type copfa deposits in the Bardaskan-Doruneh copfa belt, with a lenth of approximately 60 km in a northeast-southwest direction, host more than ten active copfa mines such as Zangalu, Zarmehr, Dahane-Siah, Mehr-Ajin, Mes-e-Sorh, Cheshme Hadi, Nasim, Sepidsarw, Cheshme Marzieh and a number of mineral areas, which according to the characteristics of these types of deposits (location, genetic pattern, geometry, host rock, minerals, etc.) and their similarities with Manto type copfa deposits in Chile, Canada and the northern Michigan area, it is called as Manto-copfa deposits in Iran. Materials and MethodsThis research includes two parts of field and laboratory investigations. Field studies were carried out in a region with about 60 km in lenth. Field ofaations include surveying and searching the area, sampling and distinguishing rock units and mineralization indicators, as well as important geological features of the area. The number of 20 thin sections for lithological investigations, as well as 20 polished thin sections and 10 blocks of drill cores (examination and study of 20,000 meters of drill core related to Nasim, Zarmehr, Mes-e- Sorkh, Cheshme Hadi and Kimia mines) and surface outcrops for a map of mineralization in the area was prepared and studied. Field surveys were conducted for mineralization controllers and host rock changes in the mining pits of Nasim, Zarmehr, Mes-e-Sorkh and Cheshme Hadi mines. Also, due to the importance of tectonic structures, a structural map of the mines was prepared. Discussion and ResultsThe rock units from old to young include: Basalt, Andesite-Basalt, Andesite, Conglomerate with more volcanic fragments, Limestone, Siltstone, Marl and evaporite sediments including gypsum Marl. The general extension of this lithological sequence is northeast-southwest. Mineralization has occurred within the conglomerate unit. There are different types of conglomerate based on the size of the clasts, the lithology of the clasts, and the cement. The type of conglomerate has a great effect on mineralization and grade changes. Conglomerate is a suitable host for mineralization due to the porosity of the rock. The dip and strike of the ore body follows the dip and strike of the lithological units of the region and the deposit is of the stratibound type. Mineralization zone has a variable thickness between 2 and 6 meters (in some places, the thickness increases due to the action of faults). The dip of the ore body varies in different parts and is between 15 and 80 degrees towards the south and southeast. The mineralization texture is mostly disseminated and veined and is mainly as chalcocite mineral. In some places, due to effect of tectonic forces and the formation of fault structures, the order and sequence of units has been dislocated and messed up.Fault structures: The first group of fault structures with the northeast-east to southwest-west direction are the most important fault structures. These fault structures form the boundary between the Andesite unit and the sedimentary units and in the surface of mineralization outcrop can be seen along its lenth and it is one of the old structures in the region because it has been cut and dislocated many times by other fault structures. The second group is the north-south oriented structures and caused displacements in the mineralized host unit. This fault system, which itself consists of several parallel fault structures, has caused the creation of secondary spaces and the intensification of mineralization, and as a result, the grade has increased in some parts of the region by joining these parallel faults together and with deepening of the basin the intensity of mineralization has increased.The third group of fault structures with the northwest-southeast direction are right lateral strike-slip and minor left lateral strike-slip faults. These structures are one of the most important fault structures in the region, which displaced the rock units of the region, especially the host of mineralization. AcknowledgmentsThis Research has been done with Financial Support of the vice President for Research and Technology of Ferdowsi University of Mashhad under Project No.59745/3 in date 2024/4/19. We would like to thank the Komeh Mine Pars Company, Parsi kan kav Company, Mehad Company and the Tehran Oxin Zarmehr Company for coofaating and supporting this research. [ABSTRACT FROM AUTHOR]

The entrance of the Madre de Dios convent in Seville was carved in stone by Juan de Oviedo y de la Bandera, an important sculptor who made great artistic productions, highlighting his carvings in wood and stone. Several studies have been carried out on the carvings in wood, but no interest has been paid by experts to the carving pieces in stone. In this work, this polychrome made on stone around 1590 was studied for the first time. Micro-samples were taken and studied using micro-analytical techniques (optical microscopy, SEM-EDX, colourimetry, XRD, FTIR, and Raman spectroscopy). The pigments (smalt, atacamite, malachite, copper resinate, cinnabar, red earth, yellow ochre, carbon, and bone black) and the consolidation product (acrylic resin, very possibly Paraloid B72) were characterized. The experimental study indicated that the polychrome was applied on a layer of white lead (cerussite and hydrocerussite) that was laid on the substrate stone, constituted by calcarenite. This study also includes a comprehensive discussion on the use of these materials and techniques in other artworks within Seville's cultural heritage. [ABSTRACT FROM AUTHOR]

The contribution of denitrifying anaerobic methane oxidation (DAMO) as a methane sink across different habitats, especially those affected by anthropogenic activities, remains unclear. Mining and industrial and domestic use of metals/metal-containing compounds can all cause metal contamination in freshwater ecosystems. Precipitation of metal ions often limits their toxicity to local microorganisms, yet microbial activity may also cause the redissolution of various precipitates. In contrast to most other studies that apply soluble metal compounds, this study investigated the responses of enriched DAMO culture to model insoluble copper compounds, malachite and covellite, in simulated sedimentary environments. Copper ≤ 0.22 µm from covellite appeared to cause immediate inhibition in 10 h. Long-term tests (54 days) showed that apparent methane consumption was less impacted by various levels of malachite and covellite than soluble copper. However, the medium-/high-level malachite and covellite caused a 46.6–77.4% decline in denitrification and also induced significant death of the representative DAMO microorganisms. Some enriched species, such as Methylobacter tundripaludum, may have conducted DAMO or they may have oxidized methane aerobically using oxygen released by DAMO bacteria. Quantitative polymerase chain reaction analysis suggests that Candidatus Methanoperedens spp. were less affected by covellite as compared to malachite while Candidatus Methylomirabilis spp. responded similarly to the two compounds. Under the stress induced by copper, DAMO archaea, Planctomycetes spp. or Phenylobacterium spp. synthesized PHA/PHB-like compounds, rendering incomplete methane oxidation. Overall, the findings suggest that while DAMO activity may persist in ecosystems previously exposed to copper pollution, long-term methane abatement capability may be impaired due to a shift of the microbial community or the inhibition of representative DAMO microorganisms.

This study measured the infrared spectra of secondary minerals in the oxidation zones of three types of copper ores: dioptase, malachite, and azurite, and assigned the peak positions of OH stretching vibrations and the origins of OH combination vibrations. Dioptase contains three types of water molecules with different orientations within its ring channels, which exhibit six kinds of OH stretching vibrations in the 3000–3600 cm−1 range; the bond length range is 2.652 to 2.887 Å. Among them, the 3443 cm−1 band shows strong near-infrared activity and combines with Si–O vibrations or OH bending vibrations in the structure, resulting in five combination vibration peaks in the 4000–5000 cm−1 range. Malachite contains two inequivalent hydroxyls in its structure, leading to two OH stretching vibrations in the high-frequency region located at 3314 and 3402 cm−1, respectively. Azurite contains only one type of hydroxyl, and thus only one characteristic OH stretching vibration is present at 3424 cm−1. The OH stretching vibrations of malachite and azurite mainly combine with [CO3]2− vibrations or OH bending vibrations, leading to six and five combination peaks in the OH combination vibration region, respectively. By analyzing the combination of peak positions at 4341 cm−1 in the near-infrared spectrum, the merged OH bending vibration at 921 cm−1 in azurite was discovered. Spectroscopic research on secondary minerals can better provide a basis for ore exploration and geological remote sensing.

The first data on the composition of rocks and precious metals in the Vasilinovskoe copper–gold–platinoid ore occurrence, new in the Polar Urals, localized in metagabbro and metapyroxenite of the Late Ordovician Kershor Complex, are presented. Rocks containing a productive gold–platinoid mineralization are confined to hydrothermal alteration zones and are mainly represented by apogabbro and apopyroxenite propylites. The propylite formation temperature obtained with the help of pyrite–pyrrhotite and chlorite geothermometers corresponds to albite–calcite–chlorite and epidote–chlorite facies and varies within 200–310°C. The ore groundmass is composed of pyrite, chalcopyrite, and magnetite. Pyrrhotite, sphalerite, cobaltite, zinc greenockite, galena, ilmenite, titanite, rutile, cinnabar, native tin, molybdenite, coloradoite, supergene minerals such as bornite and covellite, chalcocite–spionkopite minerals, malachite, azurite, and iron hydroxides are minor. The precious metal mineralization is represented by Hg-bearing gold (including Hg-electrum and Hg-küstelite), gold and silver sulfides and tellurides (sylvanite (AuAgTe4), petzite (Ag3AuTe2), acanthite (Ag2S), hessite (Ag2Te), temagamite (Pd3HgTe3), and isomorphic series minerals such as merenskyite–moncheite (PdTe2-Pt,Pd)(Te,Bi)2), stibiopalladinite (Pd5Sb2), kotulskite (PdTe), sperrylite (PtAs2), and sopcheite (Ag4Pd3Te4), intergrowths of platinoids and an unknown mineral with an idealized formula Pd(Sb,Te), and possibly a Te-rich variety of sudburyite (PdSb). According to the mineralogical data, precious metals are released after a sample is crushed to a dimension of –0.25 mm. Relatively large (<0.15 mm) gold grains are separated first, then, during the crushing of sulfides, smaller gold flakes and precious metal grains are separated. The Vasilinovskoe ore occurrence is promising in terms of gold and platinoids. [ABSTRACT FROM AUTHOR]

To liberate copper from malachite, the ore has to be reduced to appropriate size using comminution processes. Ball mills are commonly used to obtain fine particles in grinding circuits. Population balance equations can be used to model grinding kinetics in a ball mill. The aim of this study was to understand the mineralogical characteristics of malachite copper ore and identify its grinding kinetics. To achieve this, chemical analysis and petrographic studies on thin slides were carried out. Additionally, grinding tests were carried out in a ball mill using five mono-sized fractions. Short grinding cycles of 0.5 minutes were used to calculate breakage distribution functions. Longer grinding cycles up to 30 mis were used to determine specific breakage rates. The experimental results were fitted into population balance models to obtain breakage parameters that characterize the material. The parameters were used to predict particle distributions. The malachite bearing copper was found to exists among other minerals. The average concentration of copper was found to be 4.7%. The specific rate of breakage increased as particle size increased to a maximum value at particle size of 2 mm. The parameters of grinding kinetics computed parameters were applied in prediction of particle size distribution. The particle distribution produced a high degree of agreement between the simulated and experimental results. The parameters can be used in the design of ore flowsheets for processing malachite ore. [ABSTRACT FROM AUTHOR]

This study reports on experimental observations during fungi–mineral substrate interactions. Selected mineral substrates of biotite, muscovite, bauxite, chromite, galena, malachite, manganite, and plagioclase were exposed in vitro to free fungal growth under open conditions. The interaction produced strong biochemical and biomechanical alterations to the mineral substrates. Specifically, reported here is a three-dimensional thigmotropic colonization pattern of the mineral surfaces that suggested a possible pattern of fungal metalophagus behavior. Authigenic secondary mineral biomineralization occurred: Ca- and Mg-Oxalates such as weddellite: CaC2O4·2H2O, whewellite: CaC2O4·H2O, and glushinskite: MgC2O4·2H2O; struvite: (NH4) MgPO4·6H2O; gibbsite: Al(OH)3; and gypsum: CaSO4·2H2O. The bioleached elements included Fe, Pb, S, Cu, and Al, which formed single crystals or aggregates, amorphous layers, amorphous aggregates, and linear forms influenced by the fungal filaments. The fungi bioleached Fe and Al from bauxite and Mn from manganite and deposited the metals as separate mineral species. Gypsum was deposited during the interaction with the manganite substrate, indicating a source of Ca and S either within manganite impurities or within the fungal growth environment. Other biochemical and biomechanical features such as tunneling, strong pitting, exfoliation, dissolution, perforations, and fragmentation of the mineral surfaces were also produced. The results of this study, besides emphasizing the role of fungi in bioweathering and mineral alteration, also show that, to produce these alterations, fungi employ a 3D fungal colonization pattern of mineral surfaces guided by thigmotropic and possible metalophagus behavior. [ABSTRACT FROM AUTHOR]

Crystalline calcium carbonates (CCCs) are among the most widespread minerals on the Earth's surface and play a crucial role in the global carbon cycle, heavy metal sorption and incorporation. Among the numerous factors that influence the precipitation of CCCs from solution, the most determinant are the presence of additives in the mineral-forming medium, temperature, and crystallization time (aging time). The current work fills the gaps in the study of calcium carbonate crystallization from heavy metal (Me2+ = Co, Ni, Cu Fe)-containing solutions (Me2+/Ca 0.005–1.600) at different temperatures (3 and 23 °C) and aging times (21–158 days). The resulting precipitates were studied using optical and scanning electron microscopy, powder X-ray diffraction and energy-dispersive X-ray spectroscopy. Three crystalline calcium carbonates (synthetic analogues of calcite, aragonite and monohydrocalcite), as well as amorphous carbonate (AC), were found in the resulting precipitates. Temperature and aging time have a considerable effect on the phase composition, morphology and heavy metal content in CCCs. Low temperature (3 °C) and short aging times are generally favorable for the formation of monohydrocalcite and amorphous carbonate, while calcite tends to form at a higher temperature (23 °C) and in long-term experiments. Heavy metals can be incorporated into the calcite/monohydrocalcite crystal lattice in sufficient amounts, while aragonite can host a very small amount of Me2+ (or none). Calcite can concentrate Co (up to ~0.25 atoms per formula unit (apfu)) and Ni/Cu (up to ~0.05 apfu), while its Fe content is very close to the detection limits. Calcite precipitated at a higher Me2+/Ca ratio and temperature (23 °C) contains less Me2+ compared to calcite precipitated at a lower Me2+/Ca ratio and temperature (3 °C). Monohydrocalcite can host up to ~0.1 apfu of Co/Ni/Cu with no detectable preference for Me2+. The amount of Me2+ in monohydrocalcite decreases as aging time or temperature increases. It is worth noting that AC is the main carrier of heavy metals in the system being investigated and it should be considered the main host phase in heavy metal adsorption from aqueous solutions. The results obtained can be used to solve environmental issues and in mineral resource management. [ABSTRACT FROM AUTHOR]

Ringing activity in the Eastern Cape province, South Africa, spanned 30 years, with three sites active concurrently over a 14-year period, and three sites over a 6-year period. In total, in the course of 714 ringing days, in all months, we handled 1 207 Amethyst Sunbirds, 708 Southern Double-collared Sunbirds, 707 Greater Double-collared Sunbirds, 381 Grey Sunbirds, 121 Malachite Sunbirds and 140 Collared Sunbirds. Although individuals of all six species were recaptured more than five years after ringing, and despite evidence of the seasonal passage of sunbirds at two sites near the Indian Ocean coast, no birds were recaptured away from the original ringing site. The extent of seasonal movement by these species remains unclear. All species have a complete post-breeding moult, with a period of eclipse plumage in males of the Malachite Sunbird and Southern Double-collared Sunbird. Primary wing-moult in adult Greater and Southern Double-collared Sunbirds extends over three months beginning in December. Inland populations of adult Amethyst Sunbirds and Malachite Sunbirds start primary moult in April. Moult apparently proceeds more rapidly in Malachite Sunbirds (70 days to completion) than in Amethyst Sunbirds (125 days), but the Malachite Sunbird is the only species that frequently displays interrupted/suspended moult in this region. Adult Amethyst Sunbirds in the coastal population evidently start moulting earlier, in late February, with a similar duration to completion as inland birds. Juvenile Amethyst Sunbirds start to moult some two months later than adults in each region and they may complete moult more quickly. Collared Sunbirds appear to have the most protracted moult, extending over five months from November, but estimates of moult parameters for this species and the Grey Sunbird (three months from December) are based on small samples. [ABSTRACT FROM AUTHOR]

The Tamilouw-Haya orogenic gold deposit is located in the southern arm of Seram Island, Indonesia, occupying Tehoru Metamorphic Complex. Gold mineralization is predominantly in the form of veins, stockwork, and breccia, although minor dissemination is slightly appeared in the rock float samples. Ore-mineral assemblages are dominated by native gold, pyrite, chalcopyrite, sphalerite, tetrahedrite-tennantite (sulfosalt), galena, pyrrhotite, marcasite, realgar, kalininite, and arsenopyrite. Covellite, hematite, goethite, and malachite appear as supergene minerals. High-grade gold ores in this area are generally found in quartz-carbonate veins with the main alteration processes involving silicification, carbonatization, and sericitic. The P-T history of the mineralization was revealed by fluid inclusions, and this study implies the depth of ore deposit and its evolution during mineralization. The primary fluid inclusions from three different types of quartz/quartz-carbonate veins in Tamilouw-Haya crystallized at the homogenization temperature (Th) of 240 °C to 340 °C, with a fluid salinity from 3.87 to 0.70 wt. % NaCl equivalent, and melting temperature (Tm) of -0.4 to -2.3 oC. The ore-forming fluids consist mainly of two-phase (VCO2+LH2O) liquid-rich aqueous inclusions, characterized by low to rich CO2, low salinity, and moderate temperature. There are three vein types as the ore-bearing fluids with precious metals and anomalous high basemetal contents. Quartz type 1-veins (V1); concordant veins, formed at a temperature of 240-307 oC with an average salinity of 1.8 wt. % NaCl equivalent. Quartz type 2-veins (V2) tend to cut the rock foliation which are formed at temperature range from 293-336 oC with the average salinity that shows a value of 2.4 wt. % NaCl equivalent. Meanwhile, type 3 quartz-carbonate veins (V3) are formed at the temperature range of 240-340 oC and the average salinity of 2.72 wt. % NaCl equivalent. These quartz-carbonate veins cut the wall-rock foliation, which is identified as the late stage and associated with ore deposition in Tamilouw-Haya. The gold deposit in Tamilouw-Haya is formed at a depth of about 5.5-9 km of paleosurface, and the pressure between 1.7-2.4 Kbar in epizonal to mesozonal zones. [ABSTRACT FROM AUTHOR]

Molecular chaperones play vital roles in various physiological reactions by regulating the folding and assembly of biomacromolecules. We have demonstrated that cationic comb-type copolymers exhibit chaperone activity for anionic biomolecules including DNA and ionic peptide via the formation of soluble interpolyelectrolyte complexes. The development of smart artificial chaperones that can be spatiotemporally controlled by a remotely guided signal would expand the functions of artificial chaperones. Herein, to enable photocontrol of chaperone activity, a cationic comb-type copolymer bearing malachite green as a photoresponsive unit was designed. We first prepared a series of carboxylic acid derivatives of malachite green identified a derivative that could be quickly and quantitatively converted to the cationic form from the nonionic form by photoirradiation. This derivative was conjugated to the cationic comb-type copolymer, poly(allylamine)-graft-poly(ethylene glycol) through a condensation reaction. Upon photoirradiation, the copolymer bearing 9 mol% malachite green enhanced the membrane disruptive activity of acidic peptide E5 and induced morphological changes in liposomes. This demonstration of photoresponsive activation of chaperoning activity of a copolymer suggests that the installation of carboxyl derivatives of malachite green will impart photoresponsiveness to various materials including biopolymers. [ABSTRACT FROM AUTHOR]

The Goshgarchay Cu‐Au deposit is located in the central part of the northwest flank of the Murovdagh region in the Lesser Caucasus. The Goshgarchay Cu‐Au deposit is associated with Middle Jurassic volcanic and Late Jurassic–Early Cretaceous high‐K calc‐alkaline intrusive rocks. The Cu‐Au mineralization is commonly related to quartz‐sericite‐chlorite alteration dominantly composed of chalcopyrite, gold, sphalerite, pyrite, bornite, hematite, covellite, chalcocite, malachite, and azurite. The Goshgarchay copper‐gold deposit, which is 600 m wide and approximately 1.2 km long, is seen as a fault‐controlled and vein‐, stockwork– and disseminated type deposit. The Goshgarchay Cu‐Au deposit predominantly comprises Cu (max. 64500 ppm) and Au (max. 11.3 ppm), while it comprises relatively less amounts Zn (max. 437 ppm), Mo (max. 47.5 ppm), Pb (max. 134 ppm), and Ag (max. 21 ppm). The homogenization temperatures and salinities of fluid inclusions in quartz for stage I range from 380°C to 327°C, and 6.9 wt% to 2.6 wt% NaCl eq., respectively. Th and salinities in quartz for stage II range from 304°C to 253°C, and 7.6 wt% to 3.2 wt% NaCl eq., respectively. The calculated δ34Sh2s values (–1.5‰ to 5.5‰) of sulfides and especially the narrow range of δ34Sh2s values of chalcopyrite and bornite (between –0.07‰ and +0.7‰) indicate that the source of the Goshgarchay Cu‐Au mineralization is magmatic. Based on the mineralogical, geochemical, fluid inclusion, and sulfur isotopic data, the Goshgarchay Cu‐Au deposit represents a late stage peripheral magmatic‐hydrothermal mineralization probably underlain by a concealed porphyry deposit. [ABSTRACT FROM AUTHOR]

The copper-cobalt ore received from Congo contains around 2.0% copper and 0.356% cobalt, with oxidation rates of 92.09% and 88.57% for Cu and Co, respectively. Malachite and cornetite are the main copper minerals, while heterogenite and carrollite are the main Co-bearing minerals. To optimize the leaching efficiency of Cu and Co for this type of ore, various operating parameters were investigated, including particle size, pulp density, acidity, leaching time, and reductant. The recovery for Cu and Co can reach 88.36% and 74.58% under pulp density of 33%, acidity of 84 kg/t, leaching time of 4 h, and reductant 12 kg/t. In order to improve the metal recovery, an intensified operating condition (fine grinding, high acidity, and reductant) was applied, and the copper and Co recovery reached 93.07% and 89.56%, respectively. [ABSTRACT FROM AUTHOR]

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The Chahmileh Pb–Zn deposit, located northwest of the Central Iran Zone, is a sediment-hosted Pb–Zn deposit in the 'Yazd-Anarak Metallogenic Belt'. It is hosted in Middle Triassic carbonate rocks and is mainly controlled by NW-trending faults. The main ore minerals are galena and sphalerite with minor chalcopyrite, pyrite, and quartz, dolomite, along with minor calcite and baryte as gangue minerals. Cerussite, hemimorphite, wulfenite, mimetite, smithsonite, malachite and iron oxy-hydroxides are the main non-sulphide ore minerals. The main styles of mineralization are vein-veinlet, breccia, disseminated and replacement in association with silicification and dolomitization. Microthermometry of fluid inclusions in dolomite and quartz indicates that the ore precipitated from a warm to hot basin-derived saline fluid. Dolomite samples have δ13CVPDB and δ18OVSMOW values of −0.99 to +1.99‰ and +20.74 to +25.48‰, respectively, and are plotted in the marine carbonate rocks field. These isotopic values suggest that CO2 in the hydrothermal fluids mainly originated from marine carbonate rock. The δ34S values range from +6.3 to +8.2‰ for galena, +5.9 to +6.2‰ for sphalerite, +1.4 to +3.4‰ for chalcopyrite and +15.0 to +17.4‰ for bayite are compatible with a predominant thermochemical sulphate reduction process, and with sulphur sourced from Triassic seawater. Galena samples have a homogeneous Pb isotopic composition that is indicative of a continental crustal reservoir as the main source of lead and probably for the other ore metals. Based on geology, mineralogy, texture and fluid characteristics, the Chahmileh deposit is classified as a carbonate-hosted Mississippi Valley-type deposit. [ABSTRACT FROM AUTHOR]

In the Carajás Mineral Province, gossan formation and lateritization have produced numerous supergene orebodies at the expense of IOCG deposits and host rocks. The Alvo 118 deposit comprises massive and disseminated hypogene copper sulfides associated with gossan and mineralized saprolites. The hypogene reserves are 170 Mt, with 1% Cu and 0.3 ppm Au, while the supergenes are 55 Mt, comprised of 30% gossan and 70% saprolite, with 0.92% Cu and 0.03 ppm Au. The gossan includes goethite, malachite, cuprite, and libethenite zones. The saprolite comprises kaolinite, vermiculite, smectite, and relics of chlorite. In the hypogene mineralization, Ag, Te, Pb, Se, Bi, Au, In, Y, Sn, and U are mainly hosted by chalcopyrite and petzite, altaite, galena, uraninite, stannite, and cassiterite. In the gossan, Ag, Te, Pb, Se, and Bi are hosted by Cu minerals, while Au, In, Y, Sn, and U are associated with iron oxyhydroxides, in addition to Zn, As, Be, Ga, Ga, Mo, Ni, and Sc. As supporting information, δ65Cu values indicate that the gossan is immature and, at least partly, not affected by leaching. In the saprolite, Ga, Sc, Sn, V, Mn, Co, and Cr are associated with the iron oxyhydroxides, partially derived from the host rock weathering. The δ56Fe values indicate that hypogene low contribution of the hypogene mineralization to the saprolite iron content. The association of Al2O3, Hf, Zr, Th, TiO2, Ce, La, Ba, and Sr represents the geochemical signature of the host rocks, with dominant contributions from chlorites, while In, Y, Te, Pb, Bi, and Se are the main pathfinders of Cu mineralization. [ABSTRACT FROM AUTHOR]

The current work investigates the impact of magmatic fluids and metasomatic processes on the Yolindi Cu-Fe skarn deposit in the Biga Peninsula, Turkey. It traces the stages of skarn evolution, from prograde to retrograde alterations, and investigates findings within a broader geological, mineralogical, and geochemical framework. Additionally, it assesses the evolutionary history of the Yolindi deposit in relation to calc-alkaline magmatic activity in an island-arc environment and compares its mineral compositions and genesis with other global and regional Cu-Fe skarn deposits. The Yolindi Cu-Fe skarn deposit in the Biga Peninsula was formed by the intrusion of Şaroluk quartz monzonite pluton into Upper Paleozoic Torasan Formation rocks such as phyllite, schists, hornfels, marble, and serpentinites. During skarnification, reactions between the magmatic fluids from the Şaroluk quartz monzonite pluton and the Torasan Formation produced skarn minerals associated with metals such as Fe and Cu. Initially, these reactions formed prograde skarn minerals such as augite-rich pyroxenes and andradite garnets with magnetite and pyrite. As the system cooled, these initial minerals underwent retrograde alteration, leading to the formation of minerals such as epidote, actinolite, and chlorite, as well as other copper and iron minerals including chalcopyrite, bornite, secondary magnetite, and specular hematite. Therefore, four main stages influenced the formation of the Yolindi Cu-Fe deposit: metamorphic bimetasomatic, prograde metasomatic, and retrograde metasomatic stages. Later, oxidation and weathering resulted in supergene minerals such as cerussite, malachite, and goethite, which serve as examples of the post-metamorphic stage. The mineralogical shifts, such as the andradite–grossular transition, reflect changing hydrothermal fluid compositions and characteristics due to the addition of meteoric fluids. Importantly, the formation of magnetite after garnet and clinopyroxene during the retrograde stage is evidenced by magnetite crystals within garnet. The mineral associations of the Yolindi Cu-Fe skarn deposit align with the global skarn deposits and specific Turkish skarns (e.g., Ayazmant Fe-Cu and Evciler Cu-Au skarn deposits). The Yolindi Cu-Fe skarn deposit, in association with ore-bearing solutions having magmatic origins, developed in an island-arc setting. [ABSTRACT FROM AUTHOR]

A new malachite beetle, Baltamauroania mirabilicornis gen. et sp. nov., belonging to the tribe Amauroniodini (Coleoptera: Dasytidae) embedded in Eocene Baltic amber is described and illustrated. The new genus differs from the congeners of the tribe Amauroniodini in possessing a black, elongated, and subparallel body and a pronotum with scalloped lateral sides; long and 11-segmented antennae, with three apical antennomeres enlarged and forming a 'club' shape, with cylindrical antennomere 1; tarsi shortened and compressed, 5-segmented, with tarsomeres 1 and 2 equal in length, and tarsomere 5 the longest in all legs; pubescence of the dorsal surface consisting of short strong brown semi-erect and fine adpressed setae; punctation of dorsal surface irregular, elytra lacking grooves; pronotum almost equilateral, slightly elongated, with acute anterior and obtuse posterior angles, with wide margination of basal side and with scalloped and finely margined lateral sides; lateral edges of pronotum weakly rounded, with obtuse protuberance before middle. This is the second extinct genus and third record of the subfamily Danaceinae found in Eocene amber. The fossil records of the family Dasytidae are discussed. Three recent records of different Amauroniodini taxa from Eocene East European amber (Baltic and Rovno) show there to have been a high Danaceinae biodiversity in both the southern coast of the Subparatethys (documented by Rovno amber) and in its northern coast (documented by Baltic amber). The phenomenon of Danaceinae diversity in the Eocene Epoch is discussed. [ABSTRACT FROM AUTHOR]

Nucleic acid‐functionalized liposomes modified at their boundaries with o‐nitrobenzyl phosphate‐caged hairpin units and pH‐responsive C‐G·C+ triplex forming strands are used for the concomitant light and pH‐triggered fusion of three types of loaded liposomes. The fusion processes are followed by light‐scattering size enlargement measurements, optical methods, and biocatalytic cascades activated upon the mixing of the liposomes loaded with enzymes and their substrates and their fusion into the cell‐like containments. The fused liposomes act as functional protocells for the integration of biocatalytic machineries. This is exemplified by the operation of an autonomous polymerization/nickase machinery synthesizing a Mg2+‐ion‐dependent DNAzyme and of a transcription machinery yielding the Malachite Green‐RNA aptamer product. [ABSTRACT FROM AUTHOR]

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[Display omitted] • Electrochemical surface-enhanced Raman spectroscopy for identifying surface intermediates on oxide derived copper. • Strong correlation between copper carbonate hydroxide (malachite) formation and C2 product selectivity. • Local pH has an impact on the formation of the malachite phase. • CO might be strongly bound to the malachite overlayer, preventing its dimerization. We investigated the catalytic activity and C2 selectivity in electrochemical carbon dioxide reduction reaction (CO 2 RR) on two distinguished electrodeposited Cu oxides with distinct morphologies and structures. The electrode with a compact structure exhibited two times higher faradaic efficiencies of C2 products (40%). Through utilizing electrochemical surface-enhanced Raman spectroscopy (SERS), it was realized that the formation of a metastable phase (malachite) on electrode surfaces by consumption of HCO 3 - could cause a shift in local pH. The analysis of SERS indicated a strong correlation between the presence of the malachite phase and strongly-adsorbed CO on electrode surfaces, preventing dimerization and further reduction. This malachite phase terminating the surface can hinder the charge exchange and interfere with further reductions in C2 products. [ABSTRACT FROM AUTHOR]

• A fungus Simplicillium aogashimaense was discovery on artifacts for the first time. • The biological and physical destruction of the fungus caused fading of the pigments. • Simplicillium aogashimaense had the capacity of copper adsorption. • The morphology of the fungus mycelium was changed on copper-based pigments. Severe fading of the blue (azurite) and green (malachite) pigments occurred on the polychrome pottery figurines excavated from the Duan family cemetery M194 of the Tang Dynasty, in Xianyang, China, and microorganisms were suspected to be involved in this discoloration phenomenon. Therefore, molecular methods were used to identify the dominant strains isolated from azurite and malachite on the pottery figurines. On this basis, the fading mechanism of azurite and malachite from microorganisms was explored. The dominant strain was identified as Simplicillium aogashimaense , and this species has until now, not yet been encountered on cultural heritage objects. It can colonize the polychrome layers of azurite and malachite, causing the deepening of color and the thickening of mycelium after the absorption of Cu(II), resulting in the destruction of the polychrome layers. This study lays a theoretical foundation for the fading of azurite and malachite in polychrome artifacts, providing a scientific basis for their conservation. [Display omitted] [ABSTRACT FROM AUTHOR]

In general, malachite is recovered via sulfidization–xanthate flotation, although many unsatisfactory flotation indexes are frequently obtained as a result of the presence of associated calcite. This phenomenon occurs because the dissolved components of malachite and calcite affect the flotation behavior of both minerals. In this study, the effect of the dissolved components derived from malachite and calcite on the flotation behavior and surface characteristics of both minerals was investigated. Flotation tests indicated that malachite recovery decreased when the calcite supernatant was introduced, while the presence of the malachite supernatant increased the recovery of calcite. Dissolution and adsorption tests, along with zeta potential measurements, X-ray photoelectron spectroscopy, Fourier transform infrared spectrometry, and time-of-flight secondary ion mass spectrometry demonstrated that the Ca species in the calcite supernatant were adsorbed on the malachite surface, which hindered the interaction of Na2S with malachite, thereby resulting in the insufficient adsorption of sodium isoamyl xanthate (NaIX) on the surface of malachite. By contrast, the Cu species in the malachite supernatant were adsorbed on the calcite surface, and they provided active sites for the subsequent adsorption of Na2S and NaIX. [ABSTRACT FROM AUTHOR]

Horní Halže - Mýtinka is a mineral occurrence located near Mýtinka in the Krušné hory Mts. In the past, the area was intensively mined for iron (namely hematite in quartz veins). Quartz veins are located on complicated intersections of fault systems in mica schists and migmatites (Urban - Crkal 2021). Recently, Sejkora et al. (2021) described rich Cu mineralization found in the remains of old mine dumps. Sulfide mineralization is represented by pyrite, djurleite, roxbyite, anilite, spionkopite, bornite and covellite, supergene phases by malachite, brochantite, liebethenite and pseudomalachite. The studied material (thin blue coating on a part of a single sulfide grain 3 mm in size; Fig. 1) was found by the first author in 2021 at the old mine dump and matches the material described by Sejkora et al. (2021). The blue phase was identified as langite [Cu4(SO4)(OH)6 · 2H2O] using combination of EDS, Raman and pXRD. Chemical composition of examined mineral coating was analyzed using EDS, which detected presence of Cu, S and O contents only (with Cu significantly higher than S). Raman spectrum of langite from Mýtinka (Fig. 2, Tab. 1) was acquired using a HORIBA LabRam spectrometer and the data were processed using Systat PeakFit software. Proposed spectrum model is in very good agreement with empirical data (r2 = 0.992). Assignment of individual bands according to Martens et al. (2002, 2003) is proposed in Table 1. Raman spectrum of langite is similar to those of posnjakite [Cu4(SO4)(OH)6 · H2O] and wroewolfeite [Cu4(SO4)(OH)6 · H2O]. By combining (poorly and only partially presented) data of Frost et al. (2004) and Martens et al. (2002), following differences among these phases were identified. Bands at 155 and 258 (262 in this work) cm-1 are present in the Raman spectrum of langite but missing in that of posnjakite. The Raman spectrum of wroewolfeite is devoid of bands at 507 and 596 (500 and 598 in this work) cm-1, characteristic of langite, and at 511 and 596 cm-1, characteristic of posnjakite. About 15 fragments of the coating, 20-100 μm in size, were analyzed on Panalytical X'Pert powder XRD diffractometer. Only four diffraction maxima were obtained due to a very small amount of material available. Nevertheless, corresponding d-values are in a good agreement with data for langite (Tab. 2; Galy et al. 1984). [ABSTRACT FROM AUTHOR]

The aim of this investigation was to analyze the materials and techniques of the paintings in the 16th‐century ce St Mary's Church, to evaluate deterioration of the paintings, and to propose a suitable conservation treatment for their preservation. The material analysis of ground, pigments, binders, and plasters was undertaken using binocular microscopy, field emission scanning electron microscopy (SEM)–energy dispersive X‐ray spectroscopy, X‐ray fluorescence, Fourier transform infrared spectroscopy in reflectance (KBr) and transmittance mode (attenuated total reflection), thin‐film X‐ray diffraction, and micro‐Raman spectroscopy. Gas chromatography–mass spectrometry (GC‐MS) was used for identifying proteinaceous and lipidic materials extracted from the micro‐samples. The study generated data on two different red and green pigments used as decorative materials. The red pigments were identified as cinnabar along with traces of hematite and clay minerals, and green as malachite and the minor presence of other minerals. SEM analysis identified cotton fiber embedded in the coarse plaster layer that provided better strength to the plaster. Plant oils and proteins found as the binder in the pigment samples suggested that the painting technique was executed as tempera. Lead white and gypsum materials were used in previous restoration works. [ABSTRACT FROM AUTHOR]

The colors of copper-containing pigments, copper (II) oxide and malachite, and their origins in ceramic glazes were systematically examined over a wide firing temperature range using a suite of analytical and spectroscopy techniques including SEM, UV-Vis FORS, XRD, FTIR, and EPR to gain new insight into the structural and chemical transformations of the glaze during firing. The two colorants investigated were black copper (II) oxide (CuO) nanopowder and blue-green basic copper carbonate, or malachite (Cu2CO3(OH)2), both of which produce a final light blue color following firing. Additionally, silicon carbide (SiC) was used to locally reduce CuO to simulate firing glazes in a reductive environment and produce a final red color. At lower temperatures, malachite was found to decompose to form CuO at 550 °C, elucidating the reason that two different copper colorants could be used interchangeably to form the same “Robin’s Egg Blue” color. At 850 °C, a glaze sintering process occurred, resulting in the distribution of Cu2+ in a square planar geometry and an observed blue color. This structural change occurred at temperatures lower than the glaze’s melting point, indicating that complete vitrification of the glaze is not required for glaze coloration. Conversely, the reduction in Cu2+ to Cu+ through the addition of SiC did not occur until the glaze was fired above the melting temperature (1000 °C), signifying that high temperatures are required for the redox reaction to occur. This study sheds light on intermediate colorant-glaze interactions that are beneficial for understanding and predicting glaze coloring upon exposure to varying temperatures, and the results from this study can be applied to better-controlled glaze production for artists and a deeper appreciation of ceramic glaze chemistry and aesthetics.