• Economic and Environmental Geology
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• v.33 no.1
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• pp.1-18
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• 2000

Lens shaped and stratiform titanomagnetite orebodies in the Boreumdo iron mine are closely associated with amphibolite which intruded into Precambrian metasediments. Mineralogical and petrochemical analyses of amphilbolite and titanomagnetite ores were carried out in order to interpret the origin of amphilbolite and the genesis of titanomagnetite ore deposits. Amphibolites belong to orthoamphilbolite interms of Niggli value and mineralogy, and are characterized by the occurrence of relict olivine. The amphilbolites responsible for titanomagnetite mineralization have extremely high content of $TiO_2$, ranging from 2.12 to 4.59 wt.% with the average value of 3.43 wt.%. Amphibole minerals in amphibolites are consist mainly of calcic amphiboles such as hornblende, ferroan pargasitic hornblende and tremolite. Most plagioclases belong to andesine ($An_{30-50}$\ulcorner). The metamorphic temperature and geobarometric pressure which are calculated by the calcic amphibole-plagioclase geothermometer and calcic amphilbole geobarometer are estimated to be 537$^{\circ}C$~579$^{\circ}C$(avg. 555$^{\circ}C$) and 2.9~6.6 kbar (avg. 4.5 kbars), respectively. It shows a typical amphibolite facies. Based on the mineral chemistry and petrochemisty of amphibolites and iron ores which are composed mainly of titanomagnetite and ilmenite in the Boreumdo iron mine, the titaniferous oxide melts could be immiscibly separatd from the titaniferous ultrabasic magma. The genesis of the Boreumdo titanomagnetite ore deposits are analogous to the Soyeonpyeongdo and Yonchon iron ore deposits in terms of their mineralogy, mineral chemistry and geologic setting.

• Journal of Conservation Science
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• v.3 no.1 s.3
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• pp.13-18
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• 1994

Chemical analysis and metallographic observations of the iron slag were carried out in an attempt to estimate the old iron-making process. The slag containing $9.3\%\;TiO_2$ without Cu indicates that the ore used for smelting was sand iron, not rock ore. The phases identified in the slag were $ulv\ddot{o}spinel$, magnetite, $w\ddot{u}stite$, fayalite etc. This also supports the fact that the smelted ore was iron sand. The total amount of Fe and slag-making components$(=SiO_2+Al_2O_3+MgO+CaO)$ were $40.7\%\;and\;36.1\%$, respectively. These values were average ones found in the old slags formed in the ancient iron-making process. Assuming that $TiO_2$ in the ore combines with FeO, resulting in the formation of $ulv\ddot{o}spinel$, the estimated temperature of smelting was found to be about $1200^{\circ}C$.

• The Journal of the Petrological Society of Korea
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• v.18 no.4
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• pp.307-314
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• 2009

Zapla iron ore bodies in Jujuy state, northern Argentina are located within Paleozoic Silurian marine sedimentary rocks and can be categorized into ironstone deposit. Iron ores contain oolitic hematite as main iron mineral as well as siderite and chamosite. Hematite replaced biotite and/or muscovite along their cleavage or grain boundary, which indicates hematite is precipitated by chemical reaction. Silurian basins in northern Argentina has high potential resources for ironstone deposit but economic aspects of ore body can be controlled by magnitude of lateral vertical extensions and local grade variation of iron beds.

• Environmental and Resource Economics Review
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• v.19 no.2
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• pp.341-360
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• 2010

The goal of this study is to forecast the scales of seaborne trade of iron ore and coal. It is assumed that the seaborne trade of iron ore is the function of two independent variables(crude steel production, world GDP) and the seaborne trade of coal is the function of two independent variables(crude steel production, world electricity generation). The result shows that the regressions of two functions are statistically significant respectively. As the results of forecasting, the seaborne trade of iron ore in 2010 may be 892 million tons which is increased 5.1% compare to the level of 2009. Also the seaborne trade of coal in 2010 may be 827 million tons which is increased 6.1% compare to the level of 2009. In terms of the compound annual growth rate, it is forecasted that the iron ore may show 4.7% of increasing rate from 2009 to 2015 and the seaborne trade of coal may be increased 6.1% annually for the same period.

• The Korean Journal of Ceramics
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• v.2 no.3
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• pp.125-130
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• 1996

Hematite iron ore and waste iron oxide sludge containing about 3-5 wt% $SiO_2$ were purified by three types of method developed on the basis of the Bayer process which is known as the purification process of bauxite ore. The basic principle of the developed methods lies in the fact that the impurities contained in the iron oxides, such as $SiO_2$ and $Al_2O_3$ are soluble in the alkaline reagents. Reaction of the raw materials with KOH was done in pressure vessel, at atmospheric pressure, and by both of these two. By the pressure vessel method $SiO_2$ content was reduced to below 0.5 wt% in the waste iron oxide sludge, while, in iron ore, $SiO_2$ remained at 2-3 wt%. The atmospheric pressure reaction rendered the waste iron oxide sludge $SiO_2$ content below 0.5wt% when the reaction temperature increased to above 90$0^{\circ}C$. The combined method of two previous methods was the most effective process and rendered the refined iron oxide about 300-400ppm of $SiO_2$. Using some refined iron oxides, Ba-ferrite was produced and magnetic properties were measured. The highest quality of magnetic properties obtained in this study were Br=2.09 G, bHc=1.99 KOe, iHc=4.54 KOe, $(BH)_{max}$=1.06 MGOe. Effect of sintering condition and chemical composition will be discussed.

• Economic and Environmental Geology
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• v.2 no.2
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• pp.53-67
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• 1969

Magnetite deposit of Pocheon Iron Mine is a contact replacement skarn deposit embedded in the carbonate rocks (limestone and dolomite) which are intruded by granite porphyry. The shape of ore bodies is sweet potato-like and/or irregular massive form; D-ore body, the biggest one is of $180m{\times}40m{\times}200m$ in size. The ore is in general of high grade. The location of the ore bodies is controlled by the fault which strikes north south and dips $60^{\circ}$ to $70^{\circ}$ to the west. A regular distribution of mineralized zones is recognized in order of outward (hanging wall side) from granite porphyry as follows: compact fine-grained skarn, limesilicates, magnetite ore body, marble, limesilicates, pyritized meta-sediments.

• Economic and Environmental Geology
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• v.8 no.3
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• pp.165-168
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• 1975

The grade and recovery rate and its sulphur content of iron concentrate compared respectively as varied with redcued size using the Crocket Magnetic Separator and the Wet-Drum-Magnetic Separator in the magnetic separation test of iron ore from Yangyang mine. The content of sulphur was decreased distinctly as the size was finer. In case of the sample of -100 mesh, using the Crocket Magnetic Separator, the sulphur content of iron ore was decreased to 0.10% and its grade increased to 67.0%, but the recovery rate was no more than 85.1%. In the Wet-Drum type, the grade and the recovery rate of concentrate was better than those in the Crocket Magnetic Separation, but the content of sulphur was more than that in the Crocket Magnetic Separation. The Crocket type is suitable for less sulphur content while the Wet-Drum Magnetic Separator is suitable for better the grade recovery rate of the magnetic concentrate.

• Economic and Environmental Geology
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• v.12 no.1
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• pp.13-15
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• 1979

Iron ore waste discarded around Choong-ju iron district, Choongchong-Bukdo is as low as 25 per cent of iron, mainly consisting of hematite and magnetite. In this mineral dressing test procedure 93 per cent of magnetite was separated and concentrated into the magnetite concentrate as high as 62 per cent. The remaining sample, mostly, hematite averages about 19.8 per cent of iron which can be concentrated with very good results with the optimum flotation conditioning-pH 3.0 and 3 cc per litre of aero-promoter #845 (0.5% sol.) and 1.5cc per litre of hydro-fluoric acid (40% sol.) and four times of cleaning flotation. Hematite concentrate averages 64.2 per cent of iron. The overall iron concentrate averages 63 per cent of iron with recovery 86 per cent of iron contained.

• Special Issue of the Society of Naval Architects of Korea
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• 2015.09a
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• pp.85-92
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• 2015

In general, when ships are designed, structural strength and fatigue strength must be verified based on the relative rules respectively. In case of Slurry Iron Sand Carrier designed to carry Iron-Sand saturated at water content, there is no special consideration of fatigue strength analysis. However, this vessel is similar to Ore Carrier in consideration of the overall characteristics of loaded cargo and the shape of cargo hold. Therefore we verified fatigue strength based on fatigue analysis procedure of ore carrier in DNV Rules and carried out the study for improving of fatigue strength of Slurry Iron Sand Carrier.

• Geosystem Engineering
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• v.21 no.5
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• pp.262-272
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• 2018

The U-statistic method is one of the most important structural methods to separate the anomaly from background. It considers the location of samples and carries out the statistical analysis of the data without judging from a geochemical point of view and tries to separate subpopulations and determine anomalous areas. In the present study, 3D U-statistic method has been applied for the first time through the three-dimensional (3D) modeling of an ore deposit. In order to achieve this purpose, 3D U-statistic is applied on the data (Fe grade) resulted from the drilling network in Baghak mine, central part of the Sangan iron mines (in Khorassan Razavi Province, Iran). Afterward, results from applying 3D U-statistic method are used for 3D modeling of the iron mineralization. Results show that the anomalous values are well separated from background so that the determined samples as anomalous are not dispersed and according to their positioning, denser areas of anomalous samples could be considered as anomaly areas. And also, final results (3D model of iron mineralization) show that output model using this method is compatible with designed model for mining operation. Moreover, seen that U-statistic method in addition for separating anomaly from background, could be very efficient for the 3D modeling of different ore type.