Aluminosilicate Rocks Research Articles

Assessment of water supply to the east European arctic agglomeration from groundwater, taking into account their quality and health risks

The purpose of the study is to assess the possibilities of using groundwater for water supply in the East European Arctic agglomeration based on an assessment of their quality and health risks. For this purpose, high-precision determinations of the complete macro- and microcomponent composition were carried out in sixty-six water samples taken from wells up to 180 m deep. It was found that in some samples the concentrations of Na+, Fe, B, Ba, Mn and U exceeded WHO standards. The least mineralized young waters are characterized by the processes of dissolution of carbonates with the transition of Ca, Mg, Ba, Sr into water, and the processes of leaching of Fe and Mn by acidic swamp waters from near-surface sediments. Waters of high mineralization, enriched in Na+, Cl-, B, Mo, Cd, Pb, were formed as a result of the dissolution of aluminosilicate rocks over thousands of years and mixing with relics of ancient and modern marine transgressions. An assessment of the average Water Quality Index value of the studied aquifer showed that, in general, the water is of excellent quality. Non-carcinogenic risks were determined primarily by uranium concentrations. The average danger index values for this element for children were 1.22. In adults it was slightly lower and amounted to 0.83. Carcinogenic risks are associated primarily with arsenic concentrations. The average total carcinogenic risk associated with this element was 3.8.10−5, which is acceptable, but samples from two wells showed total carcinogenic risk values above 10−4, which is in the high-risk area. For drinking purposes, it is preferable to use low-mineralized water with a minimum content of toxic elements. If necessary, preliminary aeration of the water is possible, during which precipitation of iron, arsenic and uranium occurs. Due to the typical nature of the problem under consideration for the Arctic regions, the results obtained can be used at other sites in the Subpolar zone.

Genesis of Carboniferous aluminous-bearing strata in the northern part of the North China Craton: A case study of the Xingxian bauxite deposit

More than five billion tons of karstic bauxites were formed in the North China Craton (NCC) during the Late Carboniferous period. Compared to the bauxite ore, the genesis of the entire aluminous-bearing strata has received less attention. In this study, we conducted geological, mineralogical, and geochemical analyses on core samples from the aluminous-bearing strata located in Xingxian area, situated within the northern NCC, aiming to elucidate the genetic process of these formations. The aluminous-bearing strata consist of a bauxite layer (diaspore–anatase–kaolinite–florencite) sandwiched between the upper sandy claystone horizon (kaolinite–illite–quartz) and the lower berthierine-bearing claystone horizon (berthierine–diaspore–hematite–goethite). Based on the upper continental crust-normalized patterns of rare earth elements and yttrium (REY), immobile trace element ratios, mineral inheritance diagrams, and previous findings, it is suggested that the lower berthierine-bearing claystone was weathered from the impure limestone at the bottom, whereas the upper bauxite and sandy claystone mainly originated from intermediate-felsic igneous rocks of the northern margin of the NCC, granite from the North Qinling Orogenic Belt, and aluminosilicate rocks of the surrounding paleo-uplifts. During the early diagenetic stage, the berthierine was transformed under alkaline and reducing conditions from iron-rich clays (composed of clay minerals, ferric minerals, etc.) formed in acidic and oxidizing conditions from the underlying impure limestone. The coexistence of berthierine with low-temperature stability and diaspore is observed in the berthierine-bearing claystone, which precludes a high-temperature origin of diaspore in the aluminous-bearing strata. Moreover, diaspore is characterized by a small crystal size and is usually poorly crystallized, suggesting a supergene precipitation-diagenesis origin. The paragenetic minerals assemblages (e.g., diaspore, berthierine, goethite, hematite, etc.) suggest that the aluminous-bearing strata primarily formed in a transition zone nearer to the phreatic environment. Large-scale volcanism and warm, humid climatic conditions accelerated the decomposition of allochthonous weathering materials, resulting in the downward migration of metal ions. These ions then precipitated in a reducing and weakly alkaline environment, giving rise to form bauxite ore dominated by diaspore, anatase, and REY minerals.

РАДИАЦИОННО-ЗАЩИТНЫЙ КОМПОЗИЦИОННЫЙ МАТЕРИАЛ НА ОСНОВЕ ОТХОДОВ РУДНЫХ МИНЕРАЛОВ И КАМНЕПЕРЕРАБОТКИ

Abstract. The relevance of the research topic lies in the fact that currently there is a steady tendency to increase the amount of electromagnetic radiation (EMR) occurring in the human environment, which negatively affects the healthy indoor environment and determines the focus of experimental research on protecting humans from factors hazardous to health. This article is devoted to the possibility of creating radioprotective building materials from man-made waste from various deposits of Armenia. Research is aimed at creating a comfortable living area inside buildings through the development of radioprotective sandwich-type materials that reduce the impact of EMR on human health. Work was carried out in the direction of developing samples of radio-absorbing structures and selecting radio-absorbing fillers. The laboratory obtained samples from stone processing waste and waste from the extraction of ore minerals with a density from -1500 to 2000 kg/m3, as well as samples based on expanded perlite and a mineral binder with a density of 250-300 kg/m3 as an internal heat-insulating layer and transferred to the National Scientific Laboratory named after A.I.Alikhanyan (Yerevan Institute of Physics) for proton irradiation. In this work, the samples were subjected to proton irradiation, since it is a component of cosmic radiation, as well as EMR and is capable of penetrating through layers of matter depending on its composition and properties. Some physical and mechanical properties of the resulting materials, such as compressive strength and water absorption, were also studied. In addition, the article contains a review of foreign experience in obtaining radioprotective materials with various types of radiation. At this stage, only proton irradiation has been studied, but work in this direction continues. 
 Subject of study: development of radioprotective materials of the “sandwich” type.
 Materials and methods: waste of aluminosilicate rocks (tuffs) and waste from the extraction of ore minerals were used. The method of proton irradiation of the obtained materials was used.
 Results: radioprotective materials have been developed that reduce EMR.
 Conclusions: The possibility of obtaining radioprotective materials by introducing ore mineral mining waste into the composition of the composite material has been confirmed.

Clinker-free binders based on waste from the extraction and processing of tuff open cast mines in Armenia

The paper is related to the development of clinker-free binders based on Armenian tuff wastes, namely the Artik and Dzhraber deposits, which opencast mines are the most extensively used. Both studied rocks are mutable, which is explained by the high content of the glass phase. On their basis, it is possible to develop thermodynamically active systems that can change the state by thermal and mechanical effects using the energy of both the system itself and the environment surrounding the system, resulting in the formation of new structural bonds through hydration hardening. The compositions of clinker-free binders are given, and methods for increasing the reactivity of selected volcanic aluminosilicate rocks are investigated.

Low temperature hydrothermal processing to recover aluminum from nepheline syenite roast-leach residue

ABSTRACT Nepheline syenite is primarily an alumino-silicate rock which contains a major amount of potassium and aluminum. After potassium recovery through chloridizing roasting followed by water leaching method, the roast leach residue of nepheline syenite was considered for the aluminum extraction process due to its ample aluminum content. Sulfuric acid is chosen over other acids as it prevents the leaching of calcium. A 2^3 full factorial design was employed to study the effects of acid concentration, time, and temperature. Furthermore, to enhance the recovery and to forbid the leaching of silicon, autoclave leaching was preferred. Iron is generally leached with aluminum in the acid leaching process which could be removed effectively by pH adjustment. The leached liquor obtained after purification is evaporated by using a hot water bath. The liquor concentrated on slow evaporation to a point where aluminum sulfate started precipitating. Then, the concentrated liquor was kept overnight at 8°C in a cooling incubator. Aluminum sulfate was produced with 99.80% purity.

Preparation of Building Materials from Waste Aluminosilicate Rocks

Preparation of Building Materials from Waste Aluminosilicate Rocks

РАЗРАБОТКА ТЕХНОЛОГИИ ПОЛУЧЕНИЯ КОМПОЗИЦИОННОГО ТЕПЛОИЗОЛЯЦИОННОГО ПЕНОМАТЕРИАЛА НА ОСНОВЕ ОТХОДОВ АЛЮМОСИЛИКАТНЫХ ГОРНЫХ ПОРОД С ПОМОЩЬЮ СВЧ-НАГРЕВА

The technology of obtaining a composite heat-insulating material — foam glass, by recycling wastes of aluminosilicate rocks of Armenia, such as tuff (of different deposits), perlite and zeolite, bypassing the traditional energy-intensive high-temperature and long production process, using the method of microwave synthesis, which has many advantages compared to ordinary. Sample compositions have been developed and optimal heat treatment modes have been determined depending on the type of rock. In order to ensure the competitiveness of the material, the heat treatment process was carried out in an MWA 268 BL microwave oven in the power range from 90 to 600 W. The volumetric heating characteristic of microwave synthesis makes it possible to obtain a material with a uniform porosity and structure, as well as to significantly reduce the heat treatment time, which improves the quality of products and saves energy. The main properties of the material, such as thermal conductivity and average density, are determined.

The problem of the genesis of the Mesoarchean aluminosilicate rocks from the Karelian craton and their possible use as a quartz-feldspar raw material

The article presents original data obtained in the study of the chemical and mineral compositions of the Late Archean aluminosilicate rocks (formerly called silicites) from the Koikari and Elmus structures of the Vedlozero-Segozero greenstone belt of the Karelian craton (Central Karelia). A comprehensive study of these formations revealed their complex genesis as a result of the late imposition of hydrothermal and metamorphic alteration on sedimentary and volcanic-sedimentary rocks of feldspar-quartz composition. Due to the superimposed metasomatic (temperature?) impact on feldspar-quartz siltstones, Fe was removed from microinclusions in quartz and feldspar and its oxides were concentrated along the grain boundaries. Minerals such as monazite, parisite, allanite are also located either along the grain boundaries of quartz and feldspars, or together with calcite they fill microfractures, which makes it possible to get rid of them when preparing quartz-feldspar concentrates using various beneficiation technologies. According to most indicators limited by GOSTs, individual samples in their natural form meet the requirements for quartz-feldspar raw materials for use as part of batch in the production of diverse types of glass. Additional beneficiation of the feedstock (grinding, screening into narrow classes and further magnetic separation) leads to a decrease in Fe2O3 content to normalized values. The resulting quartz-feldspar concentrates with various particle sizes can be used in the production of building material and fine ceramics (sanitary and ceramic products, facing and finishing tiles, artistic, household porcelain and faience). The homogeneity of the mineral and chemical composition, the possibility of compact extraction and beneficiation (including in mobile small-sized installations) increase the prospects and competitiveness of this non-traditional feldspar raw material from Central Karelia.

Alteration and mineralization patterns in orogenic gold deposits: Constraints from deposit observation and thermodynamic modeling

Hydrothermal alteration and mineralization types of orogenic gold deposits display many variations depending on formation depths, types of host rock, compositions of ore fluids, spatial positions, fluid/rock ratios, and repetitive modifications during multiple fluid infiltrations in the complicated processes of fluid-rock interaction. Therefore, establishing holistic reference patterns of hydrothermal alteration with associated mineralization for the orogenic gold system is necessary. Based on the observation of typical orogenic gold deposits and thermodynamic simulation of fluid-rock reaction, the general features of proposed patterns include:(1)Orogenic ore fluids are capable of transporting sufficient gold from deep (5 kbar and 600°C) to shallow (1 kbar and 200°C) crustal levels, resulting in alteration and mineralization occurred in a much-varied depth. Only considering the effects of fluid-rock reaction and sulfidation, the formation of pyrrhotite and pyrite at relatively high and low P-T conditions, respectively, is the most important mechanism driving gold precipitation. In addition, the changes of fluid fO2 and pH can also trigger a decrease in the gold solubility in fluids.(2)Multiple waves of fluid infiltration are capable of dissolving the early-formedulfides and gold, and reprecipitate them in the distal alteration zones, which can explain the irregular gold concentration distribution patterns in wide alteration zones. The fluids under higher P-T conditions (5 kbar and 600°C and 3 kbar and 400°C) are more capable of dissolving early-formed sulfides and gold. Additionally, the later infiltrated fluids can transform early-formed pyrrhotite into pyrite.(3)The model of interactions between ore fluids and aluminosilicate rocks at varied P-T conditions indicates that the alteration mineral assemblages in hypozonal deposits (>12 km) mainly include biotite, amphibole, anorthite, K-feldspar, quartz, and pyrrhotite assemblages; that those in mesozonal deposits (6 to 12 km) are characterized by chlorite, calcite, quartz, muscovite, pyrite or pyrrhotite. The epizonal deposits (<6 km) commonly develop more abundant Fe-Mg bearing carbonates (e.g., dolomite, ankerite, and siderite), quartz, muscovite, and pyrite. The compositional variations of ore fluids and host rocks have important controls on the development of iron-oxides and carbonaceous material.(4) The alteration halo is relatively restricted under hypozonal to lower mesozonal conditions. However, broad carbonation develops under upper mesozonal to epizonal conditions, with Fe-Mg bearing carbonates and calcite distributed in proximal and distal zones, respectively.

THE USE OF ALUMINOSILICATE CLAYS AS SORBENTS IN THE PURIFICATION OF MEDIA FROM HEAVY METAL IONS

Shown that galvanic production, which is engaged in the application of protective or decorative coatings on metal and non-metal products (galvanizing, nickel plating, oxidation), can also be attributed to enterprises that pollute the environment with wastewater. Subject to all the norms of the technological process, despite the various methods of surface treatment of products, a certain amount of wastewater of complex composition is still formed. With an inferior degree of purification, they are one of the sources of pollution of aquatic environments. The main toxic components polluting this kind of wastewater are heavy metal ions such as chromium-6, cadmium-2, lead-2 and other toxic substances. Shown that in wastewater treatment the main place belongs to the sorption method, which uses natural sorbents such as activated carbons, zeolites, bentonite clays, and other natural materials. Searched for natural raw materials to obtain effective sorbents during decontamination of industrial effluents. The chemical-mineralogical composition of a number of deposits of aluminosilicate rocks in Azerbaijan has been studied. An analysis of the results obtained made it possible to establish the optimal variant of the synthesis of sorbents. Based on a frame-type aluminosilicate zeolite (clinoptilolite) and layered aluminosilicate (bentonite) with a high content of montmorillonite, their Na-forms were obtained. The results of the physicochemical analysis of the natural material and its modified Na-form are presented. Sorption treatment of wastewater from some heavy metal ions on modified forms of bentonite and clinoptilolite was carried out. It has been established that, in terms of sorption properties, the obtained sorbents based on natural raw materials Na-clinoptilolite and Na-bentonite can be recommended instead of synthetic industrial KU-2-8 in the sorption extraction of heavy metal ions from wastewater

Resource Assessment and Possible Industrial Applications of Bauxite Occurrences in Parts of the Mambila Plateau, NE Nigeria

Bauxites are normally formed from underlying aluminosilicate rocks as a result of tropical weathering. In our previous 2 papers, we presented the Geology, possible host, mineralogy, and geochemistry of the bauxites of Mambila Plateau, NE Nigeria. The bauxite was formed from residual chemical weathering of trachyte and occurs as a blanket cover over saprolite. XRD results showed gibbsite as the major mineral with small amounts of hematite, kaolinite, and quartz. Geochemistry of the bauxite ore is characterized by enriched Al2O3 (39.50-78.20.0%), erratic amounts of SiO2 (2.89-5.13%) and Fe2O3 (5.98-21.96%). In this study, the resources of Mambilla Bauxite Deposits (Block I and Block II) have been estimated to be 7,529,312.5 metric tons using block method of vertical geological cross-section bearing in mind that the Mambilla Bauxite Deposits have been explored by pitting on a regular grid pattern of 100 m×100 m. The bauxite deposit in Block II has met the requirement for metallurgical grade bauxite as standard specification (IS: 5953-1985, Reaffirmed [1]). While, Block I deposit has not met such specifications. Sustained investment in bauxite exploration is required to upgrade the ore reserves for sustainable development of a mining enterprise.

Inorganic Polymeric Materials Based on Natural Silicate and Aluminosilicate Raw Materials

The prospects of implementing the mechanochemical activation method of volcanic silicate and aluminosilicate rocks - perlites, tuffs, pumice, etc. are being considered for the production of a wide range of building materials using energy-conserving technologies. The thermodynamic and kinetic parameters of interaction in the systems of aluminosilicate – NaOH have been presented, indicating low-temperature sintering of volcanic rocks with sodium hydroxide. According to the degree of activity, the rocks have the following order: perlites, tuffs, obsidian, microcline. Kinetic parameters are presented: concentration, temperature, conversion degree, reaction rate constant, time of complete reaction and product layer thickness.

Modification of Irind Mine Pumice Surface

In the last decade, a continuous increasing research activity is focused on the surface modification of natural porous materials for the efficient removal of oil contaminants from water. A continuous in-situ oil/water separation technique for oil spill cleanup had been designed using surface modified Irind mine pumice as a sorbent. Irind mine pumice is an aluminosilicate rock, with well-developed porosity, mechanical strength, high buoyancy, chemically inert and eco-friendly, therefore it must exhibit certain water-and oil absorption capacities. The modified pumice absorbs a broad variety of oils and organic solvents with high oil absorption capacity and negligible water take-up at both static and dynamic conditions. Irind mine pumice have been used with grain sizes ranging from 2.5 ... 5.0 mm. Oligomethylhydride siloxane is used as a modifier.

Rare-earth deposits of a non-traditional type in the Azov part of the Ukrainian Shield

The geological structure and prospects of a group of rare earth objects of exogenous origin, unconventional for the Ukrainian industry, are considered. According to the authors, this is mainly the clay weathering crust of granitoids and other aluminosilicate rocks, which contains sorbed or close to them elements of the yttrium group. A feature of ores of this type that may interest investors is the possibility of relatively simple and inexpensive extraction of REE. As an example, a brief description of specific objects within the Azov part of the Ukrainian shield and on its border with Donbas is given. This is the weathering crust of subalkaline rare-metal granites of the Yekateriniv and Starodubiv massifs, aluminosilicate metamorphic rocks of the Valerianiv area, and tectonic mélange zone argillites of the Zhogoliv area. The Y-Ta-Nb type of deposits was established on the massifs, and mainly yttrium-earth deposits on the metamorphic rocks. The actual results of the analytical research made it possible to draw conclusions about the qualitative and quantitative composition of ores and forecast resources. A comparison of industrial technological methods of extracting Y and ∑REE from loose ores of the Zhogoliv ore deposit was made. The expediency of further searches and research in order to expand the mineral raw material rare earth base of Ukraine is substantiated.

Synthesis of a Colloid Additive Based on Aluminosilicate Rocks for Cement Stone Modification

Synthesis of a Colloid Additive Based on Aluminosilicate Rocks for Cement Stone Modification

Existing and promising deep processing technologies for refractory potassium-containing aluminosilicate raw materials

The paper outlines the specific concentration and processing features of refractory high-potassium aluminosilicate raw materials using the example of synnyrites and potassium feldspars. Synnyrite is an ultrapotassic rock (18&ndash;21 wt. % K2O), mainly composed of potassium feldspars (70&ndash;80 wt. %) and kalsilite (20&ndash;30 wt. %). The paper considers various deep processing scenarios for potassium aluminosilicate rocks based on alkaline and acidic methods with preliminary thermochemical or hydrochemical activation. It is shown that the nepheline method is ineffective for the processing of synnyrites due to an increase in limestone consumption, higher silica values in the raw material (over 50 wt. %) and, consequently, excessive solid waste generation. A combined technology based on sulfuric acid leaching with preliminary thermochemical activation of the original ore in the presence of magnesite or dolomite may be recommended as a promising technology for the complex processing of synnyrite. This approach reduces the sintering costs, recovers the magnesium additives consumed in the form of an additional finished product (magnesium sulfate hexahydrate MgSO4&middot;6H2O), and minimizes waste generation. Two options have been proposed for processing synnyrite into final products: the traditional approach with the output of alumina Al2O3 and potassium sulfate K2SO4, and a new approach, allowing, for the first time, to produce the more scarce aluminium magnesium spinel MgAl2O4 and potassium magnesium sulfate K2Mg(SO4)2. The new processing method for the aluminium potassium sulphates KAl(SO4)2 obtained envisages their solid-phase interaction with potash K2CO3 and brucite Mg(OH)2 (or MgO) to form MgAl2O4 and K2Mg(SO4)2.

Influence of thermoactivation on properties of mineral additives in dry mixtures

Information on the effect of thermal activation of silicate and aluminosilicate rocks used as a filler in dry building mixtures on their reactivity of interaction with lime binder is presented. The change in the distribution of acidic Bronsted and Lewis centers on the filler surface as a result of thermal activation is shown. It was found that the number of Bronsted and Lewis acid centers on the surface of fired clays exceeds the number of the same centers on the surface of unbaked clays. The number of adsorption centers at pKa from 0 to 7 and pKa> 13 on the surface of fired diatomite is 2.435 * 10-5 mol/g, and on the surface of unbaked diatomite -1.678 * 10−5 mol/g. The heat treatment of diatomite at low temperatures (2000C and 3000C) does not significantly affect the values of the compressive strength of the mortar. An increase in the firing temperature to 7000C leads to an increase in strength characteristics up to R = 4.38 MPa. However, the greatest effect is achieved when diatomite is fired at a temperature of t = 9000C. The value of the ultimate strength in compression was R = 5.1 MPa.

Investigation of the Synthesized Calcium Hydrosilicates Effect on the Properties of Energy-Saving Wall Silicate Blocks Obtained on the Basis of Technogenic Raw Materials

Currently, building blocks are widely used in the construction industry, the use of which contributes to an increase in the speed of construction several times, and also reduces labor costs. To obtain wall blocks, various binders are currently used, but the use of composite binders obtained on the basis of new types of raw materials, is relevant. Among the currently non-used natural raw materials, it is possible to single out aluminosilicate rocks, unconventional for the construction industry, characterized by the presence of clay rocks of mineral formation unfinished stage (aggregates) in their composition. Based on the results of the studies carried out, the effect of the synthesized calcium hydrosilicates addition was established as СSH (I) and С2SH(A) on the properties of energy-saving wall silicate blocks obtained on the basis of technogenic aluminosilicate raw materials. The rational content of the СSH (I) additive is 1.5 wt. %, which contributes to an increase in the products’ strength by 30-50%. The optimum lime content in the raw mix is 12 wt. %. The nature of the influence С2SH(A) on the properties of non-autoclave silicate materials obtained by the method of injection technology, in general, coincides with the addition of CSH (I). The resulting material can be used as a structural material (non-supporting structures) inside low-rise buildings and structures. Low average density of this material (1300–1450 kg/m3) indicates the best thermal properties (the thermal conductivity coefficient of the samples is 0.17 W/m·K).

Metasomatism and cyclic skarn growth along lithological contacts: Physical and geochemical evidence from a distal Pb[sbnd]Zn skarn

Distal skarns form by the metasomatic reactions of a host rock induced by far-traveled hydrothermal fluids. Physical and structural characteristics and geochemical patterns of distal PbZn skarn bodies were studied at the Petrovitsa deposit in southern Bulgaria. Skarn bodies formed from the interaction of hydrothermal fluids with reactive host lithologies (marble and gneiss). These fluids were transported along sub-vertical feeder structures and lithological contacts. Epidote skarn developed in gneiss protolith, and pyroxene (johannsenite) skarn developed in marble. Detailed geological mapping, complimented by measurements of the internal structure of the skarn body using pyroxene growth versors, quantifies the propagation direction of the skarn body: 1) away from the major local fluid conduit (feeder structure), and 2) away from lithological contacts between aluminosilicate rock and marble. Such growth suggests that fluid flow was generally orthogonal to the skarn front propagation direction in the pyroxene skarn.Textural, mineralogical and geochemical data from skarn samples reveal multiple growth generations of major skarn calc-silicates epidote and pyroxene. The epidote skarn is characterized by limited spatial distribution and fine-grained epidote/clinozoisite growth associated with massive replacement and sulfide mineralization. The pyroxene skarn consists of acicular clinopyroxene crystals which form spheroidal aggregates with discrete growth banding. These bands are the physical representation of the cyclic fluid pulses which resulted in rhythmic skarn growth marked by geochemical banding. In situ geochemical analyses in the epidote skarn reveal early Al-rich epidote overprinted by Fe-rich epidote associated with higher Mn and Sr contents and irregular compositional banding. Clinopyroxene (Jo60–95) shows general increase in Na, Al, Mn, and REE + Y with distance from the feeder structure and lithologic contacts. These elements correlate with the distance traveled by the hydrothermal fluid from the feeder to the site of skarnification, which we define using a proxy based on the Al content of pyroxene crystals. This reflects an increasing degree of fluid “contamination” by interaction with the aluminosilicate host rocks and functions as a proxy for fluid transport distance. The spatial distribution of trace-elements in pyroxene on an outcrop scale is indicative of discrete pulses of hydrothermal fluid resulting in precipitation of skarn calc-silicates along the increasingly tortuous fluid pathway between the feeder structure and the skarn front, resulting in both the macro- and micro-scale chemical and textural variability of the skarn body.

Water Absorption Capacity of Irind Mine Pumice

Water absorption capacity of Irind mine pumice depending on the particle size and absorption time is presented in the paper. Irind pumice is an aluminosilicate rock, with well-developed porosity, mechanical strength, high buoyancy, chemically inert, eco-friendly and exhibits sufficient water absorption capacities. The examination of the pumice by X-ray diffractometry has shown that it is a volcanic rock and is composed of cristobalite and coesite. The following particle sizes were selected for the study: 1.5… 2.0 mm, 2.5 ... 5.0 mm. Water absorption capacity of pumice was determined depending on the absorption period. The maximum water absorption was observed for particle sizes ranging from 2.5 to 5.0 mm.