고진석 Chin Surk Ko , 톡토흐마 B. Togtokhmaa , 박천영 Cheon-young Park

DOI: Vol.31(No.2) 67-73, 2018

The objective of this study was to investigate the application of sulfate solvents for the economic and eco-friendly leaching of valuable metals from Au concentrate using an acid bake-water leaching system (AWS). AWS experiments were performed using an electric furnace with various baking temperatures (100-500℃) and sulfate solvents (H₂SO₄, K₂SO₄, (NH₄)₂SO₄, MgSO₄, and CaSO₄). The efficiency of the valuable metal leaching increased as the baking temperature was increased to 400℃. Based on the AWS leaching time experiments, the maximum leaching rate occurred with the aqueous (NH₄)₂SO₄ solvent. This study demonstrates that aqueous (NH₄)₂SO₄ could be used as an effective solvent for valuable metal leaching using an AWS.

유용금속, acid bake, 수침출, 황산염용매제, 황산암모늄, valuable metal, water leaching, sulfate solvents, (NH₄)₂SO₄

임정화 Jeong Hwa Lim , 유재형 Jaehyung Yu , 배성지 Sungji Bae , 고상모 Sang-mo Koh , 박계순 Gyesoon Park

DOI: Vol.31(No.2) 75-86, 2018

This study analyzed precipitation environment, heavy metal concentration, mineral composition, and spectral characteristics associated with heavy metal concentration and mineral composition for the reddish brown precipitates occurred in the drainage of Dogye mining station. The pH of the reddish brown precipitates ranges from 7.59 to 7.94 resulting neutral. XRF analysis reveals that the precipitates has high Fe concentration, and contaminated with Ni, Cu, and Zn. Dolomite, calcite, goethite, magnetite, kaolinite, pyrophyllite, quartz and aluminum isopropoxide were identified based on XRD analysis. As a result of spectral analysis associated with heavy metal contamination, visible reflectance increases and infrared reflectance decreases with a increase in heavy metal concentration. The spectral characteristics of the reddish brown precipitates is turned out to be manifested by goethite, magnetite, kaolinite, pyrophyllite and aluminum isopropoxide.

도계광업소, 적갈색침전물, 침전환경, 중금속 오염, 분광학적 특성, Dogye mining station, reddish brown precipitation, precipitation environment, heavy metal contamination, spectral characteristics

유현민 Hyunmin Yu , 신동복 Dongbok Shin

DOI: Vol.31(No.2) 87-101, 2018

The Manjang deposit developed in the Hwajeonri formation of the Okcheon metamorphic belt consists of the Central and Main orebodies of Cu-bearing hydrothermal vein type and the Western orebody of Fe-skarn type. This study focuses on the Cu mineralization of the Central and Main orebodies to compare with the genetic environments of the Western orebody previously studied. The Central orebody produced pyrrhotite and chalcopyrite as major ore minerals with vein texture, while the Main orebody contains pyrite, arsenopyrite, and chalcopyrite as major ore minerals with vein, massive, and brecciated texture. Sphalerite, galena, magnetite, ilmenite, rutile, cassiterite, wolframite, and stannite are also accompanied. Local occurrence of skarn is dominated by grossular and hedenbergite, reflecting the reduced condition of the skarnization. Geothermometries of sphaleritestannite in the Central orebody and arsenopyrite-pyrite in the Main orebody indicate the formation temperature of 204-263℃ and 383-415℃, respectively. Sulfur fugacity of 10^-6-10^-7atm. in the Main orebody decreased toward the Central orebody. Sulfur isotope compositions of sulfide minerals from the Central and Main orebodies are 4.6-7.9‰ and 4.3-7.0‰, respectively, reflecting magmatic origin with slight influence by host rock. Considering ore mineralogy, texture as well as physicochemical conditions, the Main and Central orebodies of hydrothermal Cu mineralization reflect the characteristics of proximal and distal type ore mineralization, respectively, related to hidden igneous rocks, and they were generated under different hydrothermal systems from the Fe-skarn Western orebody.

만장광상, 열수맥상광체, 스카른, 동광화작용, 황안정동위원소, Manjang deposit, hydrothermal vein, skarn, Cu mineralization, sulfur isotope

정기영 Gi Young Jeong

DOI: Vol.31(No.2) 103-111, 2018

Mineralogical properties of two Asian dust (Hwangsa) samples collected during dust events in April 6 and 15, 2018 were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD analyses showed that Asian dusts were dominated by phyllosilicates (62 wt%) comprising illite-smectite series clay minerals (ISCMs) (55%), chlorite (3%) and kaolinite (4%). Nonphyllosilicate minerals were quartz (18%), plagioclase (9%), K-feldspar (3%), calcite (3%), and gypsum (2-4%). Mineral compositions determined by SEM chemical analyses were consistent with XRD data. ISCMs occur as submicron grains forming aggregate particles or coating coarse mineral grains such as quartz, plagioclase, K-feldspar, chlorite, and calcite. The ISCMs are often associated with calcite nanofibers and gypsum blades. Mineralogical properties of 2018 dusts were similar to those of previous dusts although clay contents were higher than that of coarse 2012 dust. Key words : Hwangsa, dust, mineral, X-ray diffraction, scanning electron microscopy, clay

황사, 먼지, 광물, X선회절분석, 주사전자현미경, 점토, Hwangsa, dust, mineral, X-ray diffraction, scanning electron microscopy, clay

김유미 Yumi Kim , 서현희 Hyunhee Seo , 조경남 Kyoung-nam Jo , 정다예 Da-yea Jung , 신승원 Seungwon Shin , 허민 Min Huh , 노열 Yul Roh

DOI: Vol.31(No.2) 113-121, 2018

Baekasan Acheon cave located in Hwasun-gun, Jeollanam-do is a natural limestone cave only found in this province. In this study, the mineralogical and geochemical characteristics of speleothems collected from Baekasan Acheon cave were identified and the capability of carbonate geochemical characteristics of carbonate minerals formed by the microorganisms were investigated. The samples of sediments (clay) and speleothems (shelfstone and cave coral) were collected at three sites in the cave. The samples of shelfstone and cave coral were identified mainly as carbonate mineral, Mg-rich calcite, and clay minerals were composed of quartz, muscovite, and vermiculite by X-ray diffraction (XRD) analysis. To cultivate the carbonate forming microorganisms, parts of the sediment and speleothems were placed in D-1 medium containing urea, respectively, and the growth of microorganisms was observed under the aerobic condition at room temperature. The capability of carbonate mineralization of the cultured Baekasan Acheon cave microorganisms was examined through adding 1% (v/v) of the cultured microorganisms and calcium sources, Ca-acetate or Ca-lactate, into the D-1 medium. XRD analysis showed that the microorganisms cultured in cave deposits formed calcium carbonate (CaCO₃) under all conditions, and these microbial carbonate minerals included calcite and vaterite. The morphological characteristics and chemical composition of biologically formed minerals were observed by SEM-EDS showed various crystal forms such as rhomboid, spherical, perforated surface with Ca, C, and O of major chemical components. The existence of such microorganisms in the cave can contribute the formation of carbonate minerals, and it is likely to affect the geochemical cycles of carbon and calcium in the cave.

백아산 아천동굴, 석회동굴, 탄산염형성미생물, 생지화학, 화순군, Baekasan Acheon cave, Limestone cave, Carbonate forming microorganism, Biogeochemistry, Hwasun-gun

도진영 Jin-young Do , 정종미 Jongmee Jung

DOI: Vol.31(No.2) 123-135, 2018

This study tried to find the clue to Seokrok province by comparing Seokrok used in painting culture properties with Seokrok ore from domestic occurrence and imported Seokrok ore. To this end, chemical and mineralogical characteristics of painting cultural properties were identified with portable X-ray Florescence (p-XRF), micro X-ray diffraction (micro XRD) and SEM/EDS Analysis. To obtain Pb isotopic ratio, the Pb contained in Seokrok has been analyzed with Thermal Ionization Mass Spectrometer. Atacamite (or botallackite) and small quantity of brochantite were identified from Seokrok in Dancheong, and malachite was also identified from Buddhist painting besides those two ingredients. Without distinction of type, most Seokrok used in painting cultural properties is atacamite composed of Cu and Cl. From Pb isotope analysis, it was found that Seokrok in painting cultural properties was closer to that of north Korea, north China and Japan than south Korea as in regional division for East North Asia suggested by Mabuchi. The Pb isotopic ratio of domestic green mineral belongs to the distribution of Seokrok inside the painting cultural properties but imported malachite showed considerably difference. Considering the fact that atacamite, the main mineral of Seokrok in painting cultural properties is rarely produced from southern mine of the Korean Peninsula and the result of Pb isotope analysis.

석록, 안료, 구리함유 녹색광물, 납동위원소비, 산지, Seokrok, pigment, Cu bearing green mineral, Lead isotope, Provenance study