Hematite Content Research Articles

Performance evaluation of optical sorting in mineral processing – A case study with quartz, magnesite, hematite, lignite, copper and gold ores

Optical sorting is increasingly playing an important role in mineral processing. Therefore, a better understanding of this method is required concerning general properties and mineral sorting applications. To date, optical sorting has been widely studied in terms of industrial applications and performance evaluation particularly in mineral processing. Nevertheless, process optimization requires better understanding of qualitative and quantitative figures based on real life sorting applications.In this study, the relationship between feed rate and separation efficiency of a gravity type and visible light responsive sensor mounted optical sorter (VIS sorter) was investigated. In addition to the feed rate, the effect of particle size on separation performance was also discussed. Laboratory studies included a selection of material, sample preparation, and optical sorting tests with magnesite, quartz, lignite, hematite, copper and gold ore samples. Experimental studies performed with different size fractions at varying feed rates were followed by evaluation of results with ROC (receiver operating characteristics) graphs. Recovery, grade, and capacity indicators are important to define the efficiency of the optical sorting. Alternatively, ROCs highlight missing particles and false alarm rates, which are used to characterize set points and detectability of the equipment/operation. In the tests performed with quartz and magnesite samples, % weights of valuable (white) and non–valuable (colored) particles in products were directly used to express the performance of optical sorting with ROC. Additionally, % Fe content, % dry ash content, % copper recovery and % gold recovery figures were used to define the ROC parameters for hematite, lignite, copper and gold ore samples.Results showed that the performance of the VIS type optical sorter mainly depends on correctly sorted amounts of valuable and non–valuable particles. Alongside with the evaluation of change in sorting performances in accordance with feed rate, ore type, and particle size; pre-concentration of copper and gold ores, concentration of hematite from alkaline waste, dry cleaning of lignite and market quality magnesite and quartz sorting applications with VIS type optical sorter were also discussed.

Study on the Production and Metallurgical Properties of Fluxed Pellets with High Hematite Content

An experimental study on the preparation of fluxed pellets using common and widely available iron ore and additives was conducted. The number of drops, compressive strength, and cracking temperature of green pellets with different hematite and magnetite contents were analyzed. Some pellets that exhibited good properties were heated under different conditions. The effects of heating temperature and heating time on pellet strength were studied. The low-temperature reduction, refractoriness under load, and reduction swelling of pellets, and other influencing factors were analyzed. The internal structure of the pellets was examined with a microscope. The experimental results indicate that fluxed pellets with high hematite content prepared at a laboratory are easily oxidized and exhibit lower degree of low-temperature reduction. The refractoriness under load of pellets is 50°C greater than that of acid pellets, their refractoriness-under-load range is wider (130°C), and reduction swelling is less than 15%. Our findings indicate that the product can meet the blast-furnace production requirements.

Magnetic and spectral signatures of Cerrado soils in the state of Goiás, Brazil

Abstract: The objective of this work was to estimate the iron oxide contents (hematite and goethite) and to characterize the color and the spectral and magnetic signatures of Cerrado soils in the state of Goiás, Brazil. Six Oxisols and one Inceptisol were studied. Spectral and magnetic signatures were determined by diffuse reflectance spectroscopy (DRS) and magnetic susceptibility, respectively. Then, the spectral curves and the second derivative calculations were used to determine hematite and goethite contents, as well as soil color after conversion into tristimulus values. Hematite and goethite contents were also obtained by x-ray diffractometry, and soil color was also defined in the field (Munsell color chart). The values for the isomorphic substitution of iron by aluminum and the degree of redness were also determined. DRS can be used to estimate hematite and goethite contents, as well as the color of Cerrado soils in the state of Goiás. The spectral signature can point out the main soil properties related to the contents of organic matter, iron oxides, kaolinite, and gibbsite. The magnetic signature, characteristic of soils rich in iron oxides (hematite and goethite), shows the predominance of pedogenic minerals.

Magneto- and litho-stratigraphic records of the Oligocene-Early Miocene climatic changes from deep drilling in the Linxia Basin, Northeast Tibetan Plateau

The East Asian monsoon is generally regarded to have initiated at the transition from the Late Oligocene to the Early Miocene. However, little is known about this process because of a lack of continuous strata across the boundary between the Late Oligocene and the Early Miocene in Asia. Based on previous drilling (core HZ-1) in the Miocene sediments in the southern Linxia Basin in NW China, we drilled a new 620m core (HZ-2) into the Late Oligocene strata and obtained 206m of continuous new core. The detailed paleomagnetism of the new core reveals eleven pairs of normal and reversed polarity zones that can be readily correlated with chrons 6Bn-9n of the geomagnetic polarity time scale (GPTS), define an age interval of 21.6–26.5Ma and indicate continuity from the Late Oligocene to Early Miocene. The core is characterized by the remarkable occurrence of brownish-red paleosols of luvic cambisols (brown to luvic drab soils) above reddish-brown floodplain siltstones and mudstones, which suggest that the East Asian monsoon likely began by 26.5Ma. In contrast to the siltstone and mudstone of the Late Oligocene strata, the Miocene strata begin with a thick fine sandstone bed, which marks sudden increases in erosion and loading that most likely reflect a response to tectonic uplift. The hematite content and redness index records of the core further demonstrate that the monsoonal climate in the Late Oligocene to Early Miocene in this area was mainly controlled by global temperature trends and events.

Evolution of iron crust and clayey Ferralsol in deeply weathered sandstones of Marília Formation (Western Minas Gerais State, Brazil)

Extensive flat plateaus are typical landforms in the cratonic compartment of tropical regions. Paleoclimate, pediplanation, laterization, and dissection have created complex and distinct geological, geomorphological, and pedological features in these landscapes. In the Brazilian territory, the flat plateau sculpted in sandstone of Marília Formation (Neocretaceous) belonging to the Sul-Americana surface presents a very clayey and pisolitic Ferralsol (Red and Yellow Latossolo in the Brazilian soil classification). The clayey texture of soil and the pisolites have been considered as weathering products of a Cenozoic detritical formation which is believed to overlay the Marília Formation sandstones. Using data of petrography (optical microscopy and SEM), mineralogy (RXD), and macroscopic structures (description in the field of the arrangement of horizons and layers), a complete profile of Ferralsol with ferricrete and pisolites was studied. The complex succession of facies is in conformity with a sedimentary structure of Serra da Galga member (uppermost member of Marília Formation). The hardening hematite concentration appears as layered accretions in the subparallel clayey lenses of sandstone saprolite, preserving its structure. Iron contents varied according to different soil fabrics. Higher concentrations of iron are found in the massive ferricrete or in pisolites in the mottled horizon. Kaolinite is a dominant clay mineral and shows two micro-organizations: (1) massive fabric intrinsic to the sedimentary rock, and (2) reworked in pisolites and illuviated features. The pisolites are relicts of ferricrete in the soft bioturbated topsoil. The continuous sequence of ferricrete from saprolite to the Ferralsol indicates that the regolith is autochthonous, developed directly from sandstones of Marília Formation, through a long and intense process of laterization.

Variable charges of a red soil from different depths: Acid-base buffer capacity and surface complexation model

Abstract The soil variable charges play a unique role in many soil geochemical processes, particularly soil acidification. However, due to the complicated nature of soil particles, a fundamental understanding of the acid-base buffer capacities and mechanisms is still lacking. In the present study, red soil samples from different depths were examined. The element compositions, crystal structures, and surface groups were characterized by X-ray fluorescence, X-ray diffraction, and Fourier transform infrared spectroscopy, respectively. Thermogravimetric analysis was further conducted to examine the soil compositions and the organic matter content. Kaolinite, quartz, and hematite were identified as the dominant mineral components. As the depth of the soils increased, the contents of hematite and kaolinite increased, while the contents of quartz decreased. The weight loss of the soil samples from 200 to 400 °C indicated that the organic matter decreased substantially with increasing soil depth. Based on the potentiometric titration, the pH pzc was determined to range from 4.4 to 5.0. The surface complexation model (SCM) was used to further evaluate the acid-base properties of the soils by assuming two p K a for one surface site of the bulk soil. The results showed that the values of the model-derived pH pzc were well matched with those from the titration experiments; therefore, it is feasible to apply the SCM in examining the variable charges of the bulk soils. The calculated surface site concentration H s , representing the soil buffer capacity, was positively correlated with the contents of the organic matter, implying that the organic matter of the soil plays an important role in the soil acid-base buffer capacity. From the extrapolated pH pzc , it can be proposed that kaolinite was the major soil mineral controlling the pH pzc of soils. This study would provide a quantitative approach for the soil acid-base buffer properties and a fundamental understanding of the underlying mechanisms.

Analysis of the Reduction Rate of Hematite Concentrate Particles in the Solid State by H2 or CO in a Drop-Tube Reactor Through CFD Modeling

The kinetic analysis of the reduction of hematite concentrate particles by individual reducing gas H2 or CO was performed using a computational fluid dynamics (CFD)-based approach in this paper. The particle residence time was calculated through the integration of the equation of particle motion. Non-uniform particle temperature profiles inside the reactor were obtained, and were taken into consideration for the kinetic analysis. The calculated reduction degrees based on this approach are in good agreement with the experimental values.

Experimental study on the magnetic characteristics of coal fly ash at different combustion temperatures

ABSTRACTTwo different coals containing iron minerals were combusted in a drop tube furnace at different temperatures. The ash samples collected were analyzed in detail to investigate the transformation behaviors of iron-bearing minerals and the magnetic characteristics of coal fly ash (FA). The vibrating sample magnetometer (VSM) was used to analyze the magnetic characteristics of the ash samples and Mössbauer spectroscopy was used to analyze the iron-bearing components in FA. The results indicate that combustion temperature does not significantly affect the crystals phases formed in FA, but does change the relative content of crystals. With an increase in temperature, the relative content of maghemite (γ-Fe2O3) and magnetite (Fe3O4) decreases, while the relative content of hematite (α-Fe2O3) increases. The rising combustion temperature also results in a decreasing trend on saturation magnetization of FA. Furthermore, there is a significant positive correlation between the equivalent content of iron-bearing minerals and the saturation magnetization of FA, which can be applied to remove the particulates from flue gas more efficiently.

Relationship between magnetic properties and reddening of tropical soils as indicators of weathering

This study evaluates the use of magnetic properties as an indicator of weathering of tropical soils. Soil samples collected across the tropical belt were analysed for magnetic susceptibility and its frequency dependence. Frequency dependence is caused by superparamagnetic (SP) ferrimagnetic nanoparticles, which are commonly attributed to neoformation during soil forming processes. Magnetic properties are compared to the redness rating of soil colour, which is related to the hematite content and is an established proxy for soil weathering. The investigated samples comprise material of different weathering stages from unweathered and weathered rock to subsoil and strongly weathered topsoil. They cover a broad variety of parent materials: ultrabasic, basic, intermediate, acid igneous rocks, clays and clay slates, phyllites and sandstones. The results show that soil reddening, magnetic susceptibility and in particular frequency-dependent susceptibility generally increase with proceeding weathering. However, there is a lithologic overprint and the parent material has to be taken into consideration. Soils stemming from acid igneous rocks, clays, clay slates and phyllites show a positive correlation between reddening and susceptibility or frequency dependent susceptibility, rendering these properties suitable for indicating weathering. In contrast, soils stemming from ultrabasic, basic and intermediate igneous rocks and sandstones show no significant correlation. The reason is the strong lithogenic overprint of ferrimagnetic minerals including SP particles, which commonly occur in these rock types.

The Janus face of iron on anoxic worlds: iron oxides are both protective and destructive to life on the early Earth and present-day Mars.

The surface of the early Earth was probably subjected to a higher flux of ultraviolet (UV) radiation than today. UV radiation is known to severely damage DNA and other key molecules of life. Using a liquid culture and a rock analogue system, we investigated the interplay of protective and deleterious effects of iron oxides under UV radiation on the viability of the model organism, Bacillus subtilis. In the presence of hydrogen peroxide, there exists a fine balance between iron oxide's protective effects against this radiation and its deleterious effects caused by Photo-Fenton reactions. The maximum damage was caused by a concentration of hematite of ∼1 mg/mL. Concentrations above this confer increasing protection by physical blockage of the UV radiation, concentrations below this cause less effective UV radiation blockage, but also a correspondingly less effective Photo-Fenton reaction, providing an overall advantage. These results show that on anoxic worlds, surface habitability under a high UV flux leaves life precariously poised between the beneficial and deleterious effects of iron oxides. These results have relevance to the Archean Earth, but also the habitability of the Martian surface, where high levels of UV radiation in combination with iron oxides and hydrogen peroxide can be found.

Mineralogical and geochemical trends in lateritic weathering profiles on basement rocks in Awa-Oru Ijebu and its environ, southwestern Nigeria

Three soil profiles on the basement rocks in Awa-Oru-Ijebu Igbo area of southwestern Nigeria were investigated for the formation secondary minerals and the comparison of the mineralogical and geochemical patterns in the weathering profiles overlying the rocks during the humid tropical weathering. X-ray data showed that the primary mineral constituents of the rocks such as feldspar, biotite, hornblende have altered to kaolinite and hematite. In soil horizon, kaolinite and quartz are the dominant minerals. The concentration of hematite in the laterite indicated that most of the iron oxides generated in the soil horizon have been leached into the underlying laterite layer. Kaolinite is the dominant mineral in the clayey horizon and its presence suggests that some of the iron bearing ferromagnesian minerals have altered into the kaolinite. Geochemical data further revealed significant enrichment of Al2O3 and Fe2O3 in the laterite profile compared with the parent rock, while, CaO, Na2O, K2O, P2O5 and MnO show strong depletion up the profiles. The removal of mobile elements by meteoric water and subsequent concentration of stable weathering products results in lateritization. The absence of bauxite minerals like gibbsite and diaspora in the profiles shows that the trend of weathering is towards iron enrichment (ferralitization) and not aluminum accumulation (bauxitization). The CIA values of the lateritic layers shows that the weathering process is matured and has reached advanced stage.Keywords: Basement rocks, weathering, lateritization, kaolinite, Hematite.

Characterization of ceramic ware fragments from Aizanoi-Turkey by micro Raman, XRPD and SEM-EDX spectrometry

Ceramic fragments from the antique city of Aizanoi, Turkey were investigated by micro Raman spectrometry in conjunction with XRPD and SEM-EDX analyses. Some basic physical characteristics of the ceramic samples were also investigated. Illite and muscovite were determined as the main clay types in the ceramic fragments. Clay used in the production of ceramic wares was found to be calcareous in most of the samples. No high temperature clay minerals were detected in the ceramics. All ceramic fragments were found to be rich in iron content. Hematite and magnetite were identified to be the principle coloring agents in the investigated samples. The ceramics with hematite content were assessed to be fired in an oxygen rich atmosphere whereas the samples having magnetite were proposed to be fired in an inadequately ventilated kiln. Based on the presence of calcite, dolomite and TiO2 in the crystal form of anatase in the samples, firing temperature during production was estimated to be below 750°C.

In Situ Synchrotron Powder Diffraction Studies of Reduction–Oxidation (Redox) Behavior of Iron Ores and Ilmenite

Phase transformations of two types of iron-based oxides (iron ore and industrial-grade ilmenite) were studied using synchrotron powder diffraction of the samples processed in reducing and oxidizing atmospheres at 1173 K (900 °C) and 1223 K (950 °C), respectively. In iron ore oxidation, the disappearance of the wustite and fayalite phases was followed by hematite growth and a decrease of the magnetite phase. The magnetite phase was partially recovered by treatment in a reducing atmosphere. Ilmenite oxidation initiated decomposition of the ilmenite phase with rapid growth of hematite and gradual growth of the pseudobrookite phase. In a reducing atmosphere, ilmenite was gradually recovered from pseudobrookite with a relatively fast initial decrease in rutile and hematite content. Under reducing conditions, there was interaction of iron ore with magnesio-ferrites in iron ore–ash mixture and interaction of ilmenite with silica by the formation of fayalite.

Kinetics of Thermal Transformation of Synthetic Al-Maghemites into Al-Hematites

ABSTRACT Maghemite (γ-Fe2O3) and hematite (α-Fe2O3) are important iron oxides in Brazilian soils derived from basalt. Maghemite can transform into hematite when exposed to high temperatures. However, isomorphic substitution (e.g., Al3+) may largely influence this process. We analyzed the kinetics of thermal transformation of Al-maghemites into Al-hematites and some of its mineralogical aspects. Synthetic substituted maghemites with different degrees of Al-substitution (0.0, 1.0, 2.0, 2.9, 3.8, 5.6, 6.7, 10.0, 12.0, and 17.1 mol% Al) were subjected to a temperature of 500±10 °C for 0, 5, 10, 16, 64, 128, 192, 360, 720, 2160, 3600, 5040, and 6480 min. After thermal treatment, samples were characterized by X ray diffraction (XRD), differential thermal analysis (DTA), specific surface area (SSA) measurement, and total chemical analysis. XRD patterns were analyzed by Rietveld refinement, and maghemite and hematite contents were calculated using Rietveld refinement and the method proposed by Sidhu. Isomorphic substitution of Fe by Al increased the critical temperature of transformation and the time necessary for maghemite to hematite transformation. Rietveld refinement data showed a better fit than the data adjusted by the Sidhu method. Increasing isomorphic substitution also decreased lattice parameters and mean crystallite dimension (MCD) values in maghemite; but only c-dimension and MCD decreased with increasing Al-substitution in hematite. For maghemite, the SSA increased with isomorphic substitution, rising up to 5.9 mol% Al; for hematite, SSA increased linearly. SSA decreased with heating time, regardless of isomorphic substitution.

MINERALOGIE ŽELEZNÝCH RUD Z ROZVODNÉHO VRCHU U ČABOVÉ VE STŘEDNÍ ČÁSTI ŠTERNBERSKO-HORNOBENEŠOVSKÉHO PRUHU (MORAVSKOSLEZSKÁ JEDNOTKA ČESKÉHO MASIVU)

The Čabová deposit of the Lahn-Dill type is located in the historical Beroun iron-ore district in the central part of the Devonian Šternberk-Horní Benešov Belt, consisting of metasedimentary and metavolcanic rocks (metabasites prevail). Iron ores in the district were mined mainly in the 19th century. This article summarizes the results of mineralogical research of iron ores obtained froma heap on the Rozvodný vrch Hill at Čabová. Six types of ores were distinguished: 1/ so-called jaspilite ores (ferruginous jasper with a variable content of hematite and magnetite, usually a very poor iron ore), 2/ jaspilite ores rich in magnetite and/or hematite, 3/ quartz-hematite ores, 4/ quartz-magnetite ores (stilpnomelane is oft en present), 5/ carbonate ores (siderite is an essential component, also calcite, hematite, magnetite, quartz and stilpnomelane may be present in substantial quantities), and 6/ chlorite ores (composed mainly of chamosite, which is accompanied by varying quantities of calcite, stilpnomelane, ilmenite, white mica, quartz and albite). Up to several centimetres thick veins consisting mainly of calcite and/or quartz penetrate ores. Common part of the veins are chlorite (chamosite) and stilpnomelane, less abundant are white mica, magnetite and hematite, barite is rare. Compositional chlorite geothermometers of Kranidiotis and MacLean (1987) and Zang and Fyfe (1995) yielded temperatures of formation of the oreand vein chlorites that range from 189 to 225 °C and from 206 to 267 °C, respectively (there is no fundamental difference between the chlorites of the iron ores and the veins).

Preparation of Fe2O3-TiO2 composite from Sukabumi iron sand through magnetic separation, pyrometallurgy, and hydrometallurgy

Preparation of Fe2O3/TiO2 composite from Sukabumi iron sand by magnetic separation, roasting, leaching and precipitation treatment has been carried out. Magnetic separation can separate magnetic particles and non-magnetic particles of iron sand content, while the non-magnetic particles (wustite (FeO), hematite (α-Fe2O3), maghemite (γ-Fe2O3) and magnetite (Fe3O4)) was washing with oxalic acid 1 M. The result product then was roasted at 800 °C treated by sodium carbonate (Na2CO3) addition of 1:1; 2:1 and 1:2 (w/w) of iron sand to Na2CO3 weight ratio, respectively. The X-Ray Fluorescence (XRF) analysis result shown that Sukabumi iron sand have hematite (Fe2O3) and titanium dioxide (TiO2) content about 72.17% dan 14.42%. XRD analysis of roasted iron sand shown the rutile (TiO2), Hematite (Fe2O3), NaFeO2, FeO, and Na2TiO3. Leaching of roasted iron sand using sulphuric acid (H2SO4) have influenced by concentrations of the H2SO4 solution. The optimum iron sand dissolution occurred in H2SO4 9 M, which condensation product of the leachant have a weight ratio of Fe:Ti = 1:1 (w/w). Meanwhile, the settling back-filtrate result of second condensation was obtained a ratio of Fe2O3: TiO2 of 3: 1 (w/w).

Deposição de rejeitos de minério de ferro em reservatórios: uma aplicação do método GPR

Os rejeitos gerados pela mineração de ferro no Brasil atingem volumes altos e têm aumentado em grande velocidade. Normalmente eles são dispostos em estruturas de pilhas ou em reservatórios formados por barragens de rejeitos, que demandam grandes áreas nos complexos minerários. A limitação dos recursos naturais, bem como a limitação de novas áreas para disposição de resíduos, tem levado a uma mudança de paradigma. Portanto, este trabalho teve como objetivo a aplicação de uma técnica geofísica, conhecida como Radar de penetração (GPR), para definir a existência de padrões de sedimentação na subsuperfície do reservatório criado pela barragem de rejeito do Diogo, em Rio Piracicaba, Minas Gerais, Brasil. Para auxiliar o reconhecimento dos padrões capturados pelo GPR, amostras do material da subsuperfície foram coletadas e analisadas por meio de testes de composição mineralógica, teor de umidade, condutividade elétrica, análise mineralógica e granulometria, fluorescência de Raios-X e difração de Raios-X. Os resultados indicaram que áreas com presença de rejeitos que possuem alta concentração de hematita (em torno de 60% na análise mineralógica) tiveram padrões de reflexão alterados. A presença da água gerou algumas reflexões múltiplas, que foram menos significativas em locais de menor profundidade e com maior presença de rejeito, e mais significativas em locais de maior profundidade e com menor presença de rejeitos. De uma forma geral, foi viável a aplicação do método GPR em ambientes aquáticos com subsuperfície com material depositado rico em hematita.

Evaluation of the mercaptobenzothiazole degradation by combined adsorption process and Fenton reaction using iron mining residue

ABSTRACT The present study investigated the degradation of mercaptobenzothiazole (MBT), evaluating homogeneous and heterogeneous systems. An iron mineral residue from the desliming step of iron mining was used as a source in the Fenton-like reaction (advanced oxidation process). A granulometric analysis of the residue was performed and yielded fractions with high hematite (Fe2O3) and low quartz content in sieves from 74 to below 44 mm. In this particle size range, the hematite content from 58.9% to 67.4% and the Brunauer-Emmett-Teller area from 0.1345 to 1.3137 m2 g−1 were obtained. The zeta potential curves as a function of pH were obtained for the residue, the MBT solution and mixtures thereof. The adsorption of MBT in the residue and its degradation through the Fenton-like reaction were investigated. Adsorption tests and the Fenton-like reaction were carried out, where the MBT species and the residue are oppositely charged, yielding, respectively, 10% MBT adsorption on the surface of the residue and 100% MBT degradation by the Fenton-like reaction at pH 3, hydrogen peroxide concentration of 25 mg L−1, residue concentration of 3 g L−1, 200 rpm and 25°C, from a 100 mg L−1 MBT solution. MBT degradation was found to occur mainly by the heterogeneous Fenton-like process.

Agglomeration of Hematite Concentrate by Starches

ABSTRACTStarches of varying solubilities were investigated as a partial and full bentonite replacements. They were found to be suitable for the pelletization of iron ore concentrate. When utilizing starches of varying solubility as a direct bentonite replacement, dry compression strengths increased by nearly 300 N, as compared to bentonite alone, with the highest solubility starch. This implies that on an equivalent mass basis, starch is a far superior binder than bentonite prior to 500 °C. Above this temperature bentonite became the dominating binding factor as starch had combusted and the strengths due to starch were los(t. As a partial bentonite replacement, starch again shows increasing compression strength. The highest strengths were observed where the highest solubility starches were used. Further study has indicated that starch is comprised of insoluble starch granules and soluble starch chains, the latter being the only viable binding agent.

Crystallization of MgFe2O4 from a glass in the system K2O/B2O3/MgO/P2O5/Fe2O3

Spherical magnetic Mg-Fe-O nanoparticles were successfully prepared by the crystallization of glass in the system K2O/B2O3/MgO/P2O5/Fe2O3. The magnetic glass ceramics were prepared by melting the raw materials using the conventional melt quenching technique followed by a thermal treatment at temperatures in the range 560–700 °C for a time ranging from 2 to 8 h. The studies of the X-ray diffraction, electron microscopy and FTIR spectra confirmed the precipitation of finely dispersed spherical (Mg, Fe) based spinel nanoparticles with a minor quantity of hematite (α-Fe2O3) in the glass matrix. The average size of the magnetic nano crystals increases slightly with temperature and time from 9 to 15 nm as determined by the line broadening from the XRD patterns. XRD studies show that annealing the glass samples for long periods of time at temperature ≥604 °C results in an increase of the precipitated hematite concentration, dissolution of the spinel phase and the formation of magnesium di-borate phase (Mg2B2O5). For electron microscopy, the particles were extracted by two methods; (i) replica extraction technique and (ii) dissolution of the glass matrix by diluted acetic acid. An agglomeration of the nano crystals to larger particles (25–35 nm) was observed.