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EN
Metamorphic rocks of greenstone facies (phyllites) have been discovered quite recently in the Łysogóry region of the Holy Cross Mountains. The following minerals predominate in the mineral composition of these rocks: bright mica (sericite), quartz, chlorites, rutile, pyrophyllite, xenotime, pyrite, tourmaline, apatite and monacite, while chalcopyrite, sphalerite and galena are also present in mineral veins. The phyllites from Podmąchocice are intensely tectonically deformed, while their metamorphism displays a syndeformation character. The age of the tectonic-metamorphic processes has been initially estimated based on their relation to the silicification process. The phyllites are cut by numerous hydrothermal mineral veins, including quartz-chlorite-apatite ones. These veins occur as small post-tectonic and syntaxial forms, a few centimetres long and up to 1 cm thick. In the central parts of the veins, apatite forms colourless crystals, up to 1 mm long and up to 0.1mm thick. The age of the apatites was determined by means of the laser ablation system combined with the mass spectrometer. The results of isotopic measurements were reduced using the “Vizual Age” reduction program. The U-Pb age has been estimated to ~389 ± 18 Ma (upper intercept) that points to the maximum Devonian age (Eifelian/Givetian) of formation of the quartz-apatite veins. This is the first dating that point sto hydro thermal activity of th is age in the study area. As the veins cut discordantly the metamorphic rocks, the metamorphism itself may be older than the apatite age.
EN
The synergistic effect of surfactants, i.e., Tween-80 (polyethylene glycol sorbitan monooleate), Span-80 (sorbitanoleate), and MES (fatty acid methyl ester sulfonates), on fatty acid collectors were investigated using single mineral flotation experiments, surface tension measurement, Fourier transform infrared spectrum, and contact angle measurements. The single mineral flotation experiments showed that it was possible to efficiently separate apatite from magnetite, quartz, and biotite by mixing fatty acids with surfactants. The surface tension measurement showed that the surfactants could significantly reduce the surface tension and Critical Micelle Concentration (CMC) of fatty acids. Fourier transform infrared spectroscopy analysis indicated that all of the surfactants did not react with the fatty acids, but only physically adsorbed on the surface of apatite, thus promoting the chemical adsorption of fatty acids on apatite. However, the surfactant chemisorbed on magnetite and competing with a fatty acid, which led to a decrease in the flotation recovery. The results for contact angle measurement showed that the contact angle difference between apatite and magnetite increased with the addition of surfactant, and resulted in an efficient separation.
EN
In this paper, polyaspartic acid (PASP) was exploited as a novel dolomite depressant for flotation separation of apatite and dolomite. A series of tests with Zeta potential, FTIR and XPS were used to reveal the inhibitory mechanism of PASP on dolomite. The microflotation test illustrated that PASP has a strong inhibitory impact on dolomite, and little effect on the floatability of apatite in the pH range of 9-11. When using 2.7 Mg/L PASP as the depressant under sodium oleate (NaOl) system, the flotation recovery of dolomite dropped dramatically to 9.95%, and the recovery of apatite remained at about 88.27% at pH 10. Both dolomite and apatite have calcium ion on the surface. The calcium ion on the surface of apatite were strongly inhibited and repelled by the localized anions, while the important role on the surface of dolomite was positively charged magnesium ion and localized calcium species. PASP could ionize carboxylate ion under alkaline conditions, which could chemically chelate with the exposed metal ion and be adsorbed on the surface of dolomite. And then prevent the further adsorption of NaOl onto dolomite, which greatly weaken the floatability of dolomite and enhanced the flotation separation of the two minerals.
EN
With high-grade apatite resources exhausted and economic development, enhancing the apatite quality from calcium gangue such as dolomite has a great significance for production. However, it is difficult to separate apatite from dolomite effectively due to the similar surface properties. In this study, the N-carboxybutyl chitosan (CBC) was tested as a potential selective depressant to separate apatite from dolomite in the sodium oleate (NaOL). Flotation results of single mineral and artificially mixed mineral confirmed the selective depression effect of CBC. The depression mechanism of CBC was investigated using wettability analysis, Fourier Transform Infrared (FTIR), and X-ray Photoelectron Spectroscopy (XPS) analyses. The results indicated that the CBC adsorption quantity and intensity on the dolomite surface more than that on the apatite surface, which was due to CBC absorbed on apatite surface by hydrogen bonding, while absorbed on dolomite surface mainly through chemical chelating between Ca on the mineral surface and -COO- on the depressant. These adsorption differences led to the flotation separation of the two minerals.
EN
In this paper, soluble starch was studied as a depressant of hematite during flotation separation of apatite using sodium oleate as a collector. Surface charge measurement, soluble starch adsorptions, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) were used to understand the interaction mechanisms between minerals (hematite and apatite) and soluble starch. The results indicated that chemical interaction between hematite and soluble starch was present, and supported the bonding of hydroxyl, while physical adsorption of soluble starch molecules with apatite occurred. Results of micro-flotation studies suggested that soluble starch was considered as a selective depressant for hematite. The maximum recovery difference between hematite and apatite of 77.5% was obtained with 40 mg/dm3 soluble starch. The flotation experiment results of natural iron ore showed that flotation indexes with 59.73% Fe, iron recovery of 81.5% and 75.68% of dephosphorization ratio were achieved at a soluble starch dosage of 60 mg/dm3. However, a higher dosage of soluble starch addition caused the difficulty for flotation separation of apatite from hematite. Our results provided theoretical basis for the flotation separation of apatite from iron oxide ores.
EN
Phosphatized biomorphs, resembling modern and ancient bacteria, were identified for the first time in phosphate nodules, present at the base of the Bílá Hora Formation (uppermost Cenomanian - lower Turonian), and in phosphate coprolites at the base of the Teplice Formation (upper Turonian) in the Bohemian Cretaceous Basin. They are present in colonies as filaments, coccoids, strings, rods and outgrowths, associated with the phosphate as part of the rock constituents and display the characteristics of fossilized bacteria. Two types of bacteria were identified: chemotrophic, sulphur-reducing bacteria in the phosphate nodules and phototrophic cyanobacteria in the phosphate coprolites. Microanalysis of some of the fossil bacteria revealed a fluoride-rich calcium phosphate composition, compatible with the composition of bulk samples, in which carbonate-fluorapatite is the main mineral in the phosphate nodules and coprolites. The environmental indications of these fossil bacteria support the interpretation of an anoxic environment of phosphogenesis in the latest Cenomanian - earliest Turonian and variable redox conditions of coprolite phosphatization in the late Turonian. The potential microbial role in phosphogenesis in the former may have involved the suboxic breakdown of P-rich organic matter by sulphur-reducing bacteria and the release of phosphorus in the pore water, leading to the biochemical precipitation of phosphate. The latter involved initial P-storage by phototrophic bacteria in an oxic environment, followed by P-release below the sediment-water interface under suboxic conditions and subsequent phosphatization of the coprolites.
EN
The addition of octane phenol polyoxyethylene-10 (OP-10) to oleic acid via a reagent-combination technology was carried out and it was shown that OP-10 exhibited synergistic effects in the flotation performance of oleic acid. Single-mineral flotation tests, zeta-potential measurements, total-organic-carbon determination, and scale-up of continuous tests using raw ore were also carried out. Single-mineral flotation tests showed that OP-10 exhibited virtually no collecting performance for apatite, but it improved the flotation performance of oleic acid following its addition to oleic acid in small amounts at low temperature. Zeta-potential measurements and total-organic-carbon determination results indicated that the addition of 2.5% OP-10 to oleic acid increased the absolute value of the apatite surface potential and improved adsorption of oleic acid on the apatite surface at low temperature. A scale-up of the continuous test showed that application of OP-10 with industrial fatty acids led to good synergistic effects and contributed to effective separation of phosphate ore.
EN
The constant evolution of civilisation and ever more advanced technologies have forced the global economy to search for new and renewable resources. Since the 1950s, rare earth elements (REE) have played an increasingly significant role in the production of new materials. The REE form a group of 17 elements (15 lanthanides, yttrium and scandium) with special properties that distinguish them from the other elements. These unique and essential raw materials have numerous applications nowadays. Without the rare earths, many branches of industry would not be able to function. The main resources of the REE come from the rocks with mineralization enriched in minerals with a higher REO (rare earth oxides) contents. Although there are around 270 different REE-bearing mineral species, the exploitation of the REE refers to less than 10 minerals. Five major REE minerals (the major minerals from group of bastnäsite (bastnaesite), monazite, xenotime, apatite and perovskite (loparite)) are characterized and described. The REO percentage content varies from max. 16% in apatite to max. 79% in bastnäsite. The examples shown were chosen due to their importance and level of extraction. This review-paper has been based on the compilation of data from mineralogical publications, mineralogical data websites and metallurgical articles about the alloys and their compounds.
EN
This experimental study provides important data filling the gap in our knowledge on monazite stability under conditions of fluid-mediated low-temperature metamorphic alteration and post-magmatic hydrothermal alterations. The stability of monazite and maintenance of original Th-U-total Pb ages were tested experimentally under P-T conditions of 250–350 °C and 200–400 MPa over 20–40 days. The starting materials included the Burnet monazite + K-feldspar ± albite ± labradorite + muscovite + biotite + SiO2 + CaF2 and 2M Ca(OH)2 or Na2Si2O5 + H2O fluid. In the runs with 2M Ca(OH)2, monazite was unaltered. REE-enriched apatite formed at 350 °C and 400 MPa. The presence of the Na2Si2O5 + H2O fluid promoted the strong alteration of monazite, the formation of secondary REE-enriched apatite to fluorcalciobritholite, and the formation of REE-rich steacyite. Monazite alteration included the newly developed porosity, patchy zoning, and partial replacement by REE-rich steacyite. The unaltered domains of monazite maintained the composition of the Burnet monazite and its age of (or close to) ca. 1072 Ma, while the altered domains showed random dates in the intervals of 375–771 Ma (250 °C, 200 MPa run), 82–253 Ma (350 °C, 200 MPa), and 95–635 Ma (350 °C, 400 MPa). The compositional alteration and disturbance of the Th-U-Pb system resulted from fluid-mediated coupled dissolution-reprecipitation. In nature, such age disturbance in monazite can be attributed to post-magmatic alteration in granitic rocks or to metasomatic alteration during metamorphism. Recognition of potentially altered domains (dark patches in high-contrast BSE-imaging, developed porosity or inclusions of secondary minerals) is crucial to the application of Th-U-Pb geochronology.
PL
Przeprowadzono datowania za pomocą metody trakowej i helowej dla apatytów z utworów karbońskich w Górnośląskim Zagłębiu Węglowym w celu określenia ram czasowych procesów uwęglenia. Pomierzone centralne wieki trakowe apatytów mieszczą się w przedziale od 259±11 (późny perm) do 103±6 milionów lat (wczesna kreda), a średnia długość traków waha się od 11,7±0,2 do 13,7±0,1 μm. Wszystkie wieki trakowe są młodsze od wieku stratygraficznego analizowanych próbek, wskazując znaczne zaawansowanie procesów diagenetycznych. Próbki z zachodniej i środkowej części GZW mają wieki trakowe od późnego permu do środkowego/późnego triasu (259±11 do 214±10 mln lat). Jednomodalne rozkłady długości traków i ich średnie wartości wskazują na pojedyncze, względnie szybkie zdarzenie postwaryscyjskiego wychładzania do temperatury poniżej 60°C, co jest zgodne ze znaczną erozją postinwersyjną utworów górnokarbońskich po fazie asturyjskiej. W pozostałej części mezozoiku następowało wolniejsze wychładzanie. Próbki ze wschodniej i NE części GZW mają wieki trakowe od późnego triasu do wczesnej kredy (210±10 do 103±6 milionów lat). Charakteryzuje je względnie krótsza średnia długość traków i wyższe odchylenia standardowe, a także w przypadku części próbek bimodalny i/lub mieszany charakter rozkładów długości. Jest to razem wskazówką bardziej złożonej historii termicznej, z długim okresem przebywania w PAZ i możliwym drugim zdarzeniem termicznym. Wieki helowe apatytów w całym basenie są wczesnokredowe (144,1±11 do 108,1±8milionów lat), wskazując raczej na wolne postwaryscyjskie wychładzanie lub możliwe mezozoiczne podgrzanie karbonu do temperatury nie większej niż 60–70°C, które spowodowało częściową dyfuzję helu i odmłodzenie wieków helowych, ale równocześnie nie spowodowało znaczącego zabliźniania traków na większości obszaru GZW. Jedynie w NE części GZW podgrzanie mezozoiczne mogło być nieco wyższe, do temperatury 70–85°C, powodując odmłodzenie wieków trakowych, zwłaszcza przy długim okresie przebywania w PAZ. Mezozoiczny impuls termiczny był przypuszczalnie spowodowany cyrkulacją gorących roztworów związaną z procesami ekstensji. Powyższe zakresy temperatur i czas ich występowania świadczą, że uwęglenie materii organicznej w GZW nastąpiło zasadniczo z końcem okresu karbońskiego.
EN
The apatite fission track and helium dating were used to provide a temporal framework for the coal rank data in the Upper Silesia Coal Basin. Measured apatite fission–track (AFT) central ages from sandstones and tonsteins in the USCB range from 259±11 (Permian) to 103±6 Ma (Early Cretaceous), with mean track lengths ranging from 11.7±0.2 to 13.7±0.1 μm. All AFT ages are younger than sample stratigraphic ages, indicating substantial post–depositional annealing. Samples from the western and central part of the USCB yield AFT ages of Permian to Late Triassic (259±11 to 214±10 Ma). Mean track lengths and unimodal track length distributions of these samples are indicative of a single relatively rapid Variscan cooling event to below 60°C consistent with erosion during the Asturian inversion of the basin. This was followed by slower cooling during the Mesozoic. The samples from the eastern and NE part of the USCB have AFT ages from Late Triassic to Early Cretaceous (210±10 Ma to 103±6 Ma). The relatively shorter mean track length and higher standard deviation, combined with a bimodal and/or mixed fission track length distribution in some samples, is indicative of amore complex thermal history with possibly a thermal event separated by a prolonged period in the PAZ. Apatite helium ages of samples from across the basin range from 144.1±11 to 108.1±8Ma (Early Cretaceous) indicating rather slow, post–Variscan inversion cooling or the possible mid–Mesozoic re–heating where temperatures reached only to 60–70°C. It was high enough for partial He loss from the apatite but not enough to anneal fission tracks in the most areas of the USCB. Only in the NE part of the USCB Mid–Mezozoic re-heating could be able to increase temperature to ~70–85°C causing partially resetting AFT (particularly during long stay in PAZ). Mid–Mesozoic re–heating would be caused by a hot fluid circulation related to extensional tectonic development. The timing and temperature range from thermochronological analysis imply that major coalification processes occurred in the latest Carboniferous period.
EN
This study presents apatite LA-ICP-MS U-Pb age and trace elements concentrations data from different granite types from the Tatra Mountains, Poland. Apatite from monazite and xenotime-bearing High Tatra granite was dated at 339 ± 5 Ma. The apatite LREE patterns reflect two types of magmas that contributed to this layered magma series. Apatite from a hybrid allanite-bearing diorite from the Goryczkowa Unit was dated at 340 ± 4 Ma with apatite LREE depletion reflecting the role of allanite and titanite during apatite crystallization. Apatite crystals from a hybrid cumulative rock from the Western Tatra Mountains were dated at 344 ± 3 Ma. Apatite is one of the main REE carriers in this sample and exhibit flat REE patterns. Taking into account the relatively low closure temperature of the U-Pb system in apatite (350–550°C), the c. 340 Ma apatite ages mark the end of high temperature tectonometamorphic activity in the Tatra Mountains.
PL
W kontekście coraz większego znaczenia metod izotopowych w Polsce i zrozumienia ich możliwości interpretacyjnych, przedstawiono porównanie metodyczne i wiekowe analizy trakowej i oznaczeń metodą potasowo-argonową (K-Ar) w odniesieniu do minerałów budujących skały masywu Karkonoszy oraz jego północnej osłony. Prezentowane wyniki stanowią kompilację wcześniejszych oznaczeń trakowych z obszaru karkonosko-izerskiego (Jarmołowicz-Szulc, 1984), oznaczeń K-Ar z tego samego obszaru (Jarmołowicz-Szulc i in., 2009) oraz nowszych metodycznie danych literaturowych z masywu Karkonoszy (Danišik i in., 2010). Wykazano zaletę metody trakowej, którą są przede wszystkim możliwości interpretacyjne związane z datowaniem wypiętrzenia i/lub pogrzebania w historii geologicznej skał. Pokazano również walory metody K-Ar, umożliwiającej m.in. uzyskanie wartości wieku oziębiania np. po wypiętrzeniu plutonu.
EN
Isotopic methods have been gaining their importance in Poland in last decades. The understanding on the interpretation potential of isotopic determinations of minerals has been growing up as well. In that context, age relations and methodology of the fission track and K-Ar methods have been presented based on the case of minerals forming rocks of the Karkonosze Massif and its northern metamorphic envelope. The presented results are the compilation of earlier fission track determinations from the Karkonosze-Izera Block (Jarmołowicz-Szulc, 1984), K-Ar data from the same area (Jarmołowicz-Szulc et al., 2009) and newer methodological data from the Karkonosze granitoid (Danišik et al., 2010). Advantages of the fission track method have been shown, i.e., interpretation possibilities of burial and exhumation in geological history of rocks. Importance of the K-Ar method has been presented, in that determination of a cooling age after the pluton uplift.
EN
The paper presents results of research on tonstein, which constitutes an interburden in coal seam 405 at the Sośnica - Makoszowy coal mine, Makoszowy field (mining level 600 m), Upper Silesia, southern Poland. The mineral and chemical compositions of the tonstein differ from the typical compositions described earlier for tonsteins from Upper Silesia Coal Basin area. Additionally, minerals present in the tonsteins include kaolinite, quartz, kaolinitised biotite and feldspars. The presence of the phosphatic minerals apatite and goyazite has been recognized. The presence of gorceixite and crandallite is also possible. The contents of CaO (5.66 wt%) and P2O5 (6.2 wt%) are remarkably high. Analysis of selected trace elements demonstrated high contents of Sr (4937 ppm) and Ba (4300 ppm), related to the phosphatic minerals. On the basis of mineral composition the tonstein has been identified as a crystalline tonstein, transitional to a multiplied one.
15
EN
The bromide analogue of pyromorphite Pb5(PO4)3Br was synthesized and characterized by X-ray diffraction, infrared spectroscopy and scanning electron microscopy. The solubility of the brompyromorphite was measured at 25°C and pH values of 2.0, 2.6 and 3.2. For the 3 pH measurements, the average solubility product, log KSP, for the reaction Pb5(PO4)3Br ⇔ 5Pb2+ + 3PO4 3– + Br– at 25ºC is –77.38 ± 0.70. The free energy of formation, ΔG˚f,298, calculated from this measured solubility product is –3724.7 ± 4.3 kJ mol−1. These results confirm that brompyromorphite is more soluble than pyromorphite.
EN
The reaction of Pb-adsorbed montmorillonite with aqueous solutions of PO4 and Cl ions results in the decrease in phosphate concentration associated with the formation of a new phase – pyromorphite Pb5(PO4)3Cl. Pyromorphite crystals range in size from hundreds of nm to several tens of μm, depending on the PO4, K, and Ca concentrations in the reacting system. A strong ion-exchange effect of K+ and Ca2+ cations on desorption of Pb2+ from Pb-adsorbed montmorillonite was observed. Also, a high concentration of cations leads to a rapid desorption of Pb and the formation of fine pyromorphite crystals. In contrast, low PO4, K and Ca concentrations result in the formation of relatively large euhedral crystals. Final Pb concentrations are much lower in experimental sets than in control experiments with no phosphate present.
PL
Podstawowymi metodami stosowanymi w niskotemperaturowej termochronologii basenów sedymentacyjnych są metody trakowa i helowa. Badania tymi metodami prowadzi się głównie na apatycie i cyrkonie. Metody te pozwalają na określenie czasu występowania temperatury, która ma podstawowe znaczenie zarówno poznawcze, jak i utylitarne dla powstawania złóż wielu kopalin, a także pozwala na ocenę wielu innych procesów diagenetycznych, tektonicznych oraz geomorfologicznych. Metoda trakowa opiera się na analizie defektów w strukturze minerałów, które pochodzą z rozpadu promieniotwórczych atomów _238U. Metoda helowa oparta jest na powstawaniu helu głównie z izotopów uranu i toru. Metoda helowa pozwala na ocenę temperatury w zakresie 40 do 70°C š 15°C (dla apatytu), natomiast analiza trakowa apatytów pozwala oszacować temperaturę w zakresie do około 60 do 110°C š 20°C.
EN
A fission track and actinides-helium methods arc major approaches used in a low-temperature thermo-chronology of a sedimentary basins. Measurements are carried out mainly on appetite and zircon. These methods allows to determine timing of occurrence of the temperature, which is important both for purely scientific and applied purposes, related to origin economic deposits, as well as other digenetic, tectonic and geomorphologic processes. Fission track method is based on radigenic decay of _238U, which cause radiation damage trails ("fission tracks") within minerals. The helium method is based on the production of helium mainly from isotopes of uranium and thorium. Apatite He ages provide thermo-chronologic information for temperatures between approximately 40-70°C š 15°C, whilst apatite fission track method in the range 60-1 10°C š 20°C.
EN
The studied bones and teeth of the cave bear (Ursus spelaeus) come from the Biśnik Cave, located in the Częstochowa Upland (Southern Poland). The specimens originate from different geological layers formed since the Odra Glaciation (250–270 thousand years BP). The fossilized bones and teeth were studied using optical microscopy, scanning electron microscopy, X-ray diffraction, FTIR spectroscopy, and INAA. They are built of recrystallized carbonate-rich apatite-(CaOH) and/or apatite-(CaOH). The teeth additionally contain some apatite-(CaF). The lack of collagen and minor REE contents suggest rapid burial and collagen decay in the early stage of diagenesis. The bones and teeth have only limited mineral infillings. In some teeth, Mn-Fe (hydroxy)oxides were found in the dentine canaliculi and in bones, some osteocyte lacunae contain Fe (hydroxy)oxides with admixture of Mn. In one bone specimen, calcite infillings are present in Haversian canals. The infillings formed during later stages of diagenesis and were succeeded by non-filled cracks.
EN
Natural samples of fluorite and apatite from granites, pegmatites, carbonatites and andesitic tuffs were investigated by steady-time spectroscopy to characterize the luminescence properties of Ce3+ and Eu2+. The luminescence of Ce3+ has been clearly seen in fluorite as 320 and 337 or 343 nm bands. In apatites, two distinct bands for two different Ca crystal sites were obtained: 340–380 nm for Ca(1) and 420–450 nm for Ca(2). The luminescence spectra of Eu2+ in the fluorite crystals were measured even at for low concentration of this element (0.11 ppm). For Ce3+, it has been showed that the crystal field strength depends more on the nature of the ligand than on the Me-ligand distances.
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