Fluorite Research Articles

Improving the rheological behavior of alkali-activated slag pastes by using low surface free energy mineral admixtures

This study investigates the effect of low surface free energy mineral admixtures (CaF2-dominated fluorite (FL) and fluorine-containing lithium slag (LS)) on the rheological behavior of alkali-activated slag (AAS) pastes. The fluidity, rheological behavior, surface charge properties and surface free energy properties were tested. The interparticle forces based on extended Derjaguin-Landau-Verwey-Overbeek (EDLVO) theory were calculated to understand the mechanism for the rheological behavior improvement. The results revealed that both FL and LS could improve the fluidity and decrease the yield stress and plastic viscosity of AAS pastes. Furthermore, the attraction is manifested by the sum of electrostatic, van der Waals, and Lewis acid-base forces, and this value decreases with increasing LF or LS content, implying that the particle dispersion in AAS pastes is improved. Furthermore, observing flocculent structures captured by the metallographic microscope proves the better dispersion of AAS pastes after adding FL and LS. Moreover, incorporating LS or FL decreases the flexural and compressive strengths of AAS mortars.

Bi12O17Cl2 with a Sextuple BiO Layer Composed of Rock‐Salt and Fluorite Units and its Structural Conversion through Fluorination to Enhance Photocatalytic Activity

AbstractLayered bismuth oxyhalides with bilayered (Bi2O2) fluorite (FL) slabs are promising visible‐light photocatalysts because of their excellent stability and the ability to adjust band levels depending on the layers combined. It is interesting to manipulate the Bi2O2 slab itself, but only trilayered FL blocks (e.g., Bi3O4) are reported so far. Here, a structurally uncharacterized Bi12O17Cl2, which is extensively studied as a photocatalyst for a variety of reactions, has a sextuple Bi6O8.5 block separated by Cl is shown. Unlike double and triple layered cases, the inner region of the Bi6O8.5 block contains 1D rock‐salt (RS) units in the FL matrix along the a‐axis, causing in‐plane corrugation. A topochemical reaction involving anion‐exchange gives Bi12O17–0.5xFxCl2 (x ≤ 6) with alternate FL and RS slabs along the c‐axis. The elimination of the structural corrugation increases higher photo‐conductivity and improves photocatalytic activity against acetic acid decomposition under visible light irradiation. This study paves new opportunities of controlling the properties of layered bismuth oxyhalides by the thickness of Bi–O block, FL/RS configuration, and structural modulation.

Influence of Temperature on the Defect Structure of the Fluorite Sr1 – xLaxF2 + x (x = 0.11–0.33) Single Crystals

Influence of Temperature on the Defect Structure of the Fluorite Sr1 – xLaxF2 + x (x = 0.11–0.33) Single Crystals

PROPUESTA PARA LA REHABILITACIÓN DE ÁREAS AFECTADAS POR MINERÍA DE FLUORITA. CASO DE ESTUDIO: ESTABLECIMIENTO CERROS NEGROS, CÓRDOBA, ARGENTINA

La minería, es una actividad económica relacionada a la explotación y extracción de minerales, siendo responsable de profundas modificaciones en el medio natural. A través de ella, se obtienen la mayoría de los recursos necesarios para el desarrollo de la humanidad y el bienestar social del hombre. De esta forma, es necesario plantear el desarrollo de esta actividad humana pero de forma equilibrada, asegurando la protección y conservación del medio ambiente. La relación positiva entre la extracción de recursos geológicos y la protección ambiental es posible, generando una rehabilitación y utilización del medio asegurando una puesta en valor paisajística y económica del entorno. La transferencia de rocas estériles para el relleno de huecos y el tapado de frentes rocosos junto con la reconstrucción de suelos, permiten una rehabilitación del medio en sentido estricto. El propósito de este trabajo es contribuir al conocimiento de técnicas de rehabilitación de escombreras, en el caso de estudio en una explotación minera de fluorita, Establecimiento Cerros Negros, con la generación de suelos artificiales sustentables para el desarrollo de una actividad económica agrícola.
 Palabras clave: agricultura, cantera, minería, rehabilitación, suelos.

Pink Fluorite from Inner Mongolia

Pink Fluorite from Inner Mongolia

Crystal Forms of Fluorite by Eddy van der Meersche. Self-published. 295 pages; 2013; out-of-print (hardbound)

A wise man once questioned the need for yet another book on fluorite. Well, between the covers of any book may be an enormous variety of topics, and in the case of fluorite this is particularly tru...

Faceted Fluorite

Faceted Fluorite

The effect of using different materials on erbium-doped fiber amplifiers for indoor applications

This paper investigated the different materials of optical fibers, two of them are plastic optical fibers that are namely polysulfone (PSU)/vinyl-phenyl acetate (VPAC) with refractive indices of 1.63/1.567, and the second plastic material namely sapphire (S)/polysulfone (PSU) with refractive indices of 1.77/1.63. One of the other materials consists of fluorite (FT)/polytetrafluorophenylmethacrylate (PTFPMA) with refractive indices of 1.433/1.422, where the second material consists of fluoride (FD)/poly methylmethacrylate (PMMA) with refractive indices of 1.56/1.49. Finally, the third material consists of silica (Si)/tetrafluoropropylmethacrylate (TFPMA) with refractive indices of 1.46/1.373. The simulation results are done by using optiwave simulation version 13. FT/PTFPMA fiber channel has outlined 19.23 Tb/s bit-rate with maximum Q-factor of 11.01, a minimum bit error rate of 1.05 × 10−28, gain value of 36.57 dB, and noise figure of 5.67 dB in the presence of vertical-cavity surface-emitting laser (VCSEL). It is observed that VCSEL has superior to continuous wave (CW) laser by the improvement of the performance parameters understudy at the same operating conditions.

Interação entre magmas graníticos e a origem de epissienitos potássicos estaníferos do granito Madeira, mina Pitinga, Amazonas

O estudo petrográfico de amostras da zona de contato entre as fácies albita-granito de borda e feldspato alcalino-granito hipersolvus porfirítico, na borda oeste do plúton Madeira, identificou rochas com características texturais e composicionais herdadas das duas fácies. Tal feição é interpretada como um processo de interação entre os dois magmas graníticos, colocados e cristalizados contemporaneamente. Em condições subsolidus, fluidos hidrotermais causaram alteração potássica pervasiva, ou epissienitização, caracterizada pela dissolução de quartzo das fácies graníticas, gerando cavidades e aumentando a permeabilidade das rochas alteradas. Paralelamente, a albita da fácies de borda do albita-granito foi desestabilizada e substituída por microclínio hidrotermal e, nos estágios mais tardios, as cavidades foram preenchidas por quartzo, microclínio, fluorita, hematita, cassiterita, fengita, clorita, pirita, esfalerita, galena e calcopirita. Os epissienitos potássicos são rochas de coloração vermelha escura a marrom, granulação fina a média, ricas em microclínio hidrotermal, apresentando-se ora porosas, ora com cavidades preenchidas por quartzo e sulfetos. A cassiterita das rochas epissienitizadas é mais pura e relativamente mais pobre em Nb do que aquela presente no albita-granito magmático. Os fluidos que desencadearam a epissienitização devem ter sido oxidados, ricos em K, alcalinos e subsaturados em sílica. Propõem-se duas hipóteses para a sua origem: 1) por separação de uma fase fluida a partir do líquido magmático formador do granito hipersolvus; 2) pela ação do mesmo fluido que desencadeou o processo de autometassomatismo do albita-granito de núcleo, gerando sua fácies de borda.

Control of Radiation Sensitivity of the Oxygen-Containing Fluorite Crystals

Control of Radiation Sensitivity of the Oxygen-Containing Fluorite Crystals

STUDY OF INDIGENOUS FLUORSPAR AS METALLURGICAL FLUX

The mineral reservoirs of Pakistan have an enormous amount of Fluorspar. Approximately 1 million ton reservoir of Fluorspar was reported previously and is mostly exploitable. Also, around one third of its usage is in the form of metallurgical flux, a key slag fluidizer in steel industry as it increases the fluidity of slag in the ladle furnace. However, it needs to undergo beneficiation process to get it concentrated before being added into the furnace. In this study, we report, for the first time in Pakistan, that the indigenous Fluorspar can directly be used as a metallurgical flux without any beneficiation process as it is rich in Fluorite and also contains small amount of other compounds that are required to be fed as part of slag. Specifically, it contains only trace amount of apatite as compared to global Fluorspar. The composition of indigenous Fluorspar was compared with standard specifications and a detailed characterization was carried out including chemical, mineralogical, and spectroscopic analysis. Further, indigenous Fluorspar was applied as flux in the ladle refining operation of a local steel mill of Pakistan and results were stated on the basis of degree of desulphurization and different basicity indexes

Evaluation of fluoride enrichment processes in groundwater of Chimakurthy granitic pluton complex in Prakasam District India

Hydrogeochemical evaluation of aquifers belonging to Chimakurthy granitic pluton complex reveals wide spatial and temporal variation in F- distribution. F- concentration in groundwater of different aquifers varies from 1in almost all the samples of three sampling sessions establish silicate weathering. Ca2+/Mg2+, Na+/Ca2+, Ca2+, Mg2+ and HCO3- ratios authenticate carbonate dissolution is responsible for alkali earths addition. Sodic rich and calcium depleted water together with balanced alkalinity has enabled F- enrichment. Presence of fluorite as accessory mineral apart from occurrence of F- in mineral lattice of biotite, hornblende, muscovite, and pyroxene were the potential sources of F- to the percolating pore waters. Though F- was abundantly available in solid solution the receptive hydrochemical character of solute was governing the F- adsorption which could be one of the strong reasons for uneven distribution of F- with in similar petrological setup. Key words: Water-rock interaction, fluoride, groundwater, Chimakurthy, gabbro, hydrogeochemistry.

ENERGY RESOURCES AND ECONOMIC DEVELOPMENT OF RUSSIA

Russia is rich in energy reserves that are essential to an industry and in a household use. Its mineral wealth is abound with various raw materials such as earth oil, natural gas, coal of every geological types and metamorphose phases (from pure humic coal to boghead coal and from liptobiolith to friable lignite), iron stone, uranium, aurum and others. Russia has the exceptional mineral resources pool. The specificity of the Russian raw-material base is a complexity. The base is included almost all types of minerals: fuel-power reserves (oil, gas, coal, uranium); ferrous metals (iron, manganese, chromian stones); nonferrous and rare metals (cuprum, plumbum, zink, nickelic, aluminium materials, algam, wolframite, molybdenum, stibnic, azoque, titanium, zirconium, niobium, tantalum, yttrium, rhenium, scandium, strontium and others); precious metals (aurum, argentums, platinoids) and rough diamonds; non-metals (apatites, phosphorites, potash and sodium salts, fluor spar, mica, talcum, magnesium, mineral carbon, baryta, piezo-optic raw materials, precious and ornamental stones and others). The mineral potential of Russia is totally suffice for adopting and independent and effective policy. The country-produced mineral base is instrumental in the world commodities-based industries. Raw materials provide the economic and defensive strength of the country. The mineral raw materials and end products, which have been produced due to sand mining and following mineral processing, constitute the chief export earner of Russia. Russia is rich in energy reserves that are essential to an industry and in a household use. Its mineral wealth is abound with various raw materials such as earth oil, natural gas, coal of every geological types and metamorphose phases (from pure humic coal to boghead coal and from liptobiolith to friable lignite), iron stone, uranium, aurum and others. Russia has the exceptional mineral resources pool.

Vibrational spectrum and XPS contrastive studies on pyrochlore-type oxygen-rich Ce2Zr2O8 and oxygen-defective Nd2Zr2O7 phases

Pyrochlore-type oxygen-rich Ce2Zr2O8 phase was prepared successfully by graphite reduction method. With the oxygen[U8]-defective Nd2Zr2O7 substituting for the oxidized precursor phase CeZrO3.5+Δ was carried out the structure comparative analysis with Ce2Zr2O8. The X-ray diffraction (XRD), Raman spectroscopy (Raman), infrared spectroscopy (IR) and X-ray photoelectron spectroscopy (XPS) were used to characterize the crystal structure of samples. The XRD experimental results show that Ce2Zr2O8 bulk phase contains the typical structure of pyrochlore, the superstructure peaks that characterize Ce/Zr cations ordering arrangement are very obvious, but the Zr-O ligands had also transformed from octahedrons of the co-top connection in the precursor to cubes of co-edge connection in the Ce2Zr2O8, and the formation of [ZrO8] ligand reduced greatlly the structural stability of Ce2Zr2O8 phase. Raman and IR results show that vibrational spectra bands of Ce2Zr2O8 phase increased significantly, meaning that the enriched oxygen ions result in a removal of the degeneracy peak for Ce2Zr2O8 phase, which confirms further the structural symmetry of Ce2Zr2O8 phase lower than its precursor. XPS results show that Ce (IV) characteristic peak (916.3 eV) in the Ce2Zr2O8 phase surface is very obvious. No the appearance of Ce (III) peak (885 eV) suggests that Ce3+ from the precursor has been completely oxidized into Ce4+ in the Ce2Zr2O8 phase; the Zr(3d) binding energy is close to fluorite phase with Zr4+, which confirms that [ZrO8] ligand in the Ce2Zr2O8 surface is consistent with the bulk phase. The increasing low binding energy of O(1s) shows that oxygen species in the Ce2Zr2O8 bulk phase are between lattice oxygen and adsorbed oxygen, the presence of high oxygen peak suggests that the surface of Ce2Zr2O8 contains adsorbed oxygen, and the bonding strength between adsorption oxygen and Ce2Zr2O8 bulk phase is between CeO2 and Nd2Zr2O7.

Donnayite-(Y) from the Albyn gold deposit, Russian Far East

515 The rare hydrous Y, Sr, Ca, and Na carbonate don� nayite�(Y) (Sr, Ba) 3(Y,Ca,Na)3[CO3]6 ⋅ 3H2O was first found in a pegmatite dike cutting across syenite of the Mont St.�Hilaire Massif in Quebec, Canada [1]. Until recently the mineral was known to occur only in rocks of alkaline complexes: along with St.�Hilaire, these were the Khibina Massif in the Kola Peninsula and the Vishnevye Gory Massif in the Urals [2, 3]; the mineral was also found in carbonatite in the Khibina and Vuor� ijarvi massifs in the Kola Peninsula [4, 5]. In derivatives of alkaline rocks, donnayite�(Y) is contained together with microcline, calcite, natrolite, aegirine, and more rare Sr, Ba, and REE carbonates. Donnayite is occasionally accompanied by albite, fluo� rite, barite, minerals of the labuntsovite group, and its Ba analogue mackelveyite.

Polymetallic mineralization of the Boranja orefield, Podrinje Metallogenic District, Serbia: zonality, mineral associations and genetic features

In the Serbo-Macedonian Metallogenetic Province, which is a part of the Alpine metallogenic unit, the ore deposits lie in number geotectonic units; they embrace part of the Vardar Zone, Serbo-Macedonian massif, and a small part of the Dinarides. This metallogenic province has been delineated mostly by reference to the Neogene metallogeny, related predominantly to granodiorite magma. These deposits include the most significant Pb-Zn and Sb deposits in Serbia, as well as smaller Bi, Mo, Cu, Fe, Sn, Au and minor U, W and Hg deposits. The Podrinje Metallogenic District belongs to the Serbo-Macedonian Metallogenetic Province. Smaller metallogenic provinces are isolated within the scope of the following orefields: Cer (Northwest Serbia), Boranja (West Serbia), and Srebrenica (East Bosnia & Herzegovina). Polymetallic deposits in the Boranja orefield are genetically related to the emplacement of a Tertiary granodiorite complex. It consists primarily of a large number of sulfide deposits with Pb-Zn, and Sb; with subordinate Cu, As, Bi and Ag. Among them, the presence of small magnetite deposits, connected to the pyrometasomatic (skarn) stage is significant. Skarns are of calcic type, and were formed along contacts of Triassic limestones and quartz diorites. Ore minerals are similar among the various types of orebodies in the Boranja orefield and consist of sulfides (pyrrhotite, pyrite, marcasite, chalcopyrrhotite, chalcopyrite, cubanite, mackinawite, valleriite, covelline, chalcocite, bismuthinite, molybdenite, sphalerite, mercurian sphalerite, greenockite, galena, arsenopyrite, stibnite, duranusite, realgar, orpiment, cinnabar, metacinnabar); sulfosalts (bursaite, cannizzarite, cosalite, aikinite, ustarasite, tetradymite, ferrian tetrahedrite, argentian tetrahedrite, pyrargyrite, diaphorite, freieslebenite, schirmerite, fizelyite, stannite, jamesonite, boulangerite, bournonite, As-bournonite, falkmanite, zinkenite, fuloppite, robinsonite, plagionite, twinnite, geocronite, gratonite); telluride (calaverite); native metals and alloys (gold, silver, electrum, bismuth, arsenic); oxides and complex-oxides (magnetite, hematite, rutile, anatase, scheelite, powellite, valentinite, senarmontite, kermesite, adamite, arsenolite); and gangue minerals (silicates, carbonates, fluorite, calcite, siderite, Mn-Zn siderite, fluorite, apatite, barite, dolomite, anglesite, cerussite, smithsonite, otavite, malachite, azurite, scorodite, quartz, limonite, organic matter). Minerals of the titled orefield were formed in several successive stages, which together correspond to a unique cycle of mineralization that is genetically related to the subvulcanic-plutonic intrusion of the Neogene-aged magmatic Boranja complex. Mineral associations, which have spatial-zonal arrangement, are rhythmically developed from the Tertiary granodiorite of Boranja to outside surroundings: A) Fe-Cu(Bi) belt → B) Pb(Ag)-Zn belt → C) Sb(As) belt → D) CaF 2 (Pb-Zn) belt.

Age and material sources of lithium-fluorine granites of the Far East (U-Pb and Lu-Hf isotope data)

The increase in the thickness and evolution of the composition of the Earth's crust in the range from 1.8 to 0.1 Ga resulted in growth of the scales of intraplate granitoid magmatism and progressive increase of the number of intrusions of lithium-fluorine granites (1). The youngest of them are registered in the granitoid provinces of the eastern margin of Asia, such as Verkhoyanskaya, Chukotskaya, Khingano-Okhot� skaya, and Sikhote-Alin'skaya (2). The authors present the results of investigation of the age and material source of raremetal granitoids of th eFar East on the basis of a complex study of the Lu-Hf and U-Pb isotope systems in zircon and with account for modern ideas on the geochemical evolution of the Earth's crust (3). Small intrusions of raremetal lithium-fluorine granites located in the apical parts of biotite leucog� ranite domes were revealed during geological mapping of the ore regions of the Far East. The most studied are the Dozhdlivyi stock in the eastern endocontact of the Verkhneurmiiskii massif (Badzhal'skii region, Pria� mur'e) and the series of sheet deposits in the Severnyi massif (Kuiviveem-Pyrkakaiskii region, Chukotka) (4, 5). They associate with thin (<0.5 m) dykes of ongonite, elvan, and porphyry monzogranite compos� ing the Urmiiskii (Priamur'e) and Ichuveemskii (Chukotka) dyke belts. Lithium-fluorine granites are represented by mediumand finegranular micro� cline-albite varieties with zinnwaldite, topaz, and flu� orite. Accessory minerals are represented by zircon, monazite�(Ce), fluocerite, ilmenite, wolframoixiolite, struverite, samarskite�(Yb), xenotime�(Y), allanite� (Y), fergussonite�(Y), and chernovite�(Y). According to the results of Rb-Sr dating, Li-F granites of the Verkheurmiiskii and Severnyi massifs have a Late Cretaceous age: 83.4

Mexican Fluorite

Mexican Fluorite

The Weardale Giant: A Large Fluorite Specimen Recovered from the Rogerley Mine, Weardale Northern England, July 2012

10.1080/00357529.2013.747894-F0001 Figure 1. The first portion of the fluorite specimen exposed in the pocket, 12 July. Jesse Fisher photo. 10.1080/00357529.2013.747894-F0002 Figure 2. Map of Weard...

Trace Element Characteristics of Fluorite and Its Sm-Nd Isotopic Dating in Getang Gold Deposit, Guizhou Province

Trace Element Characteristics of Fluorite and Its Sm-Nd Isotopic Dating in Getang Gold Deposit, Guizhou Province