• Economic and Environmental Geology
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• v.27 no.4
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• pp.325-333
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• 1994

Gold and/or silver mineralization in the southeast province, Korea, occurred in hydrothermal quartz vein that fills fracture zones in Cretaceous volcanic and sedimentary rocks of the Gyeongsang basin or granites and Precambrian gneiss. Most of the gold-silver-bearing veins in the province occur in Hapcheon, Suncheon and Haman-Gunbuk area where they are associated with Cretaceous Bulgugsa granites. On the basis of the Ag/Au ratio on amounts produced and ore grades, mode of occurrence, and associated mineral assemblages, hydrothermal Au-Ag deposits in southeast province, Korea, can be classified as follows: pyrite-type gold deposit (Group IIB, Samjeong and Sangchon deposits), antimony-type gold-silver deposit (Group IV, Gisan and Geochang deposits), and antimony-type silver deposit (Group V, Sanggo, Seweon, Seongju and Gahoe deposits). All of the gold-silver deposits in the province are generally characteristics of the gold-silver or silver-dominant type deposit which contains more silver-bearing minerals than those deposits in central Korea. The gold-silver mineralization in the deposits consist of two generation; the early characterized by gold precipitation and the late represented by silver-rich (as silver-bearing sulfosalts minerals) mineralization. All but one deposit (Samjeong deposit) having relatively lower Au content in electrum values between ${\approx}20$ and ${\approx}50$ atomic %. The mineralogical data on electrum-sphalerite and/or arsenopyrite geothermometry and fluid inclusion data indicate that the gold and silver mineralizations were occurred at temperatures of $190{\sim}280^{\circ}C$ and $150{\sim}180^{\circ}C$, respectively. These suggest that the gold-silver mineralization in the province occurred in the lower temperature and pressure conditions as epithermal-type hydrothermal vein deposit.

• Journal of the Korean Society of Costume
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• v.63 no.7
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• pp.79-93
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• 2013

In the Korean literature, records of systematic gold thread manufacturing such as gold foil(金 箔匠), gold foil bonded with fabrics(付金匠), gold foil bonded with paper materials(金箋紙匠), refining gold(鍊金匠), cutting gold(裁金匠), and making gold thread(絲金匠) can be easily found. We can infer from these literatures that the Korean people used to make gold threads. However, is not existent the gold thread making technique. Thus, a research was done using 67 pieces of gold thread artifacts used in textiles craft of Korea, China and Japan. The purpose of this research was to identify the characteristics of the Korean gold thread by studying the artifacts' form classification, gold foil, glue and the base. First, gold thread is divided into flat gold thread and wrapped gold thread. Wrapped gold thread was made in more various methods such as with a paper on the flat gold thread, metal thread and wrapped gold thread with gold foil on top. Compared to the flat gold thread, wrapped gold thread uses a thread that has a thinner and wider. Through this analysis, even making of the base of the gold threads was different according to the type. Secondly, we looked into the characteristics of materials according to form structure of the gold thread. After analysis of experiment results, we could know that to attach Korean gold thread, glue and the mixture of materials such as Red soil(朱土) was also added. The kinds of the base of gold threads were identified as paper, leather and intestines. Among those materials, for paper, Korea's Dakji, China's Sangpiji(桑皮紙) and Jukji(竹紙) and Japan's Anpiji(雁皮紙) seemed to have all been used, so because of the difference among countries, we can prove that Korea has also produced gold thread. By looking at the research, the base of gold threads and making features hugely vary according to the area.

• Journal of the Mineralogical Society of Korea
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• v.23 no.1
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• pp.1-13
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• 2010

The Yugeum deposit in Youngduk in Gyungsangbuk-do is emplaced in the Cretaceous granitoids located in the Northeastem Gyeongsang Basin. Gold-bearing quartz veins filling the fracture with a direction of $N19^{\circ}{\sim}38^{\circ}W$ are most abundantly distributed within the Younghae granodiorite body. The formation of quartz veins can be classified into three main stages: barren quartz stage, auriferous quartz vein stage, and finally the extensive sulfide mineralization stage. Various sulfide minerals such as pyrite, chalcopyrite, galena, sphalerite, and arsenopyrite were precipitated during the hydrothermal gold mineralization process. Gold commonly occurs as fine-grained electrum in sulfides with high Au concentration (up to 93 wt%) compared to Ag. During the early gold mineralization stage, the temperature and pressure of the fluids are in the range of $220{\sim}250^{\circ}C$ and 730~1800 bar, and the oxygen fugacity is between $10^{-27}$ and $10^{-31.7}$ atm. On the other hand, the fluids of the late stage mineralization are characterized by temperature of $290{\sim}350^{\circ}C$ and pressure of 206~472 bar, and the oxygen fugacity is in the range of $10^{-26.3}{\sim}10^{-28.6}$ atm. The sulfur isotope compositions of sulfide minerals are in the range of $0.2{\sim}4.2^{\circ}/_{\circ\circ}$, while the ${\delta}^{34}SH_2S$ values range from 1.0 to $3.7^{\circ}/_{\circ\circ}$. The Ag/Au atomic ratios of electrum ranges from 0.15 to 1.10, and Au content is higher than Ag in most electrum. During the main gold mineralization stage at the relatively high temperature condition and with pH from 4.5 to 5.5, the stability of ${AuCl_2}^-$ increased while the stability of ${Au(HS)_2}^-$ decreased. Considering the pressure estimated in this deposit, the temperature of the ore fluid reached higher than $350^{\circ}C$ and ${AuCl_2}^-$ became an important species for the gold transportation. As mineralization proceeded with decreasing temperature and increasing pH and $f_{o2}$, the precipitation of sulfide minerals and accompanying electrum occurred.

• Research in Plant Disease
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• v.12 no.1
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• pp.25-27
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• 2006

Rice dwarf phytoreovirus (RDV), a member of the family Reoviridae has a genome composed of 12 segmented dsRNAs designated as 51 to 512 with an increasing order of mobility in polyacrylamide gel electrophoresis (PAGE). RDV encode 12 structural and non-structural proteins, $P1{\sim}P12$ which are encoded by the $S1{\sim}S12$ segments of the dsRNA genome, respectively. In this experiment, we confirmed in situ localization of RDV particles and P12 in cytoplasm of infected rice plant. We observed specific reaction of the gold particles using virus particle and P12 protein specific antiserum with protein A-gold immunolabelling in electron microscope. It was observed that gold particles specifically react to virus particles in cytoplasm in case using the antiserum for virus particles. In the case of antiserum for P12 protein, gold particles sporadically existing on cytoplasm without existing in organelle of cytoplasm specifically. As this result, RDV P12 protein encoded by S12 located in cytoplasm.

• Economic and Environmental Geology
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• v.31 no.2
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• pp.89-99
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• 1998

The gold-silver mineralizations in Korea are closely related to Jurassic Daebo igneous activity (121 and 183 Ma) and Cretaceous Bulgugsa igneous activity (60 and 110 Ma). A compilation and re-evaluation of chemical data in arsenopyrite suggest that the As contents vary, reflecting different genetic environments or mineral assemblages. The gold-silver vein deposits from various mineralized area were investigated using arsenopyrite geothermometer. Arsenopyrites from the Jurassic Au-dominant deposits are distinct by high As contents (29.68~33.46 atomic %) with narrow variations, equivalent to a temperature range of $370{\sim}450^{\circ}C$ and a sulfur fugacity of about $10^{18}-10^{-6}$ atm. On the contrary, arsenopyrites from the Cretaceous Au-Ag and Ag-dominant deposits show a wider range in atomic % As composition of 27.47-32.74. They may have formed at temperatures of $250{\sim}350^{\circ}C$ and about $f_{S_2}=10^{-12}-10^{-10}$ atm. The data of arsenopyrite geothermometer, electrum-sphalerite geothermometer, fluid inclusions, vein morphology and emplacement depth of igneous rocks indicate that the gold mineralizations of Group IIA occurred at temperatures between 300 and $500^{\circ}C$ at depth of several tens km or more (about 4-5 kbar), and the gold-silver deposits of Groups III, IV and V were formed at a temperature range of about $170{\sim}370^{\circ}C$ under the shallow environment (<1 kbar).

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.2
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• pp.179-194
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• 2020

A Bayesian approach was introduced to improve the belief of prior distributions of input parameters for the probabilistic safety assessment of radioactive waste repository. A GoldSim-based module was developed using the Markov chain Monte Carlo algorithm and implemented through GSTSPA (GoldSim Total System Performance Assessment), a GoldSim template for generic/site-specific safety assessment of the radioactive repository system. In this study, sequential Bayesian updating of prior distributions was comprehensively explained and used as a basis to conduct a reliable safety assessment of the repository. The prior distribution to three sequential posterior distributions for several selected parameters associated with nuclide transport in the fractured rock medium was updated with assumed likelihood functions. The process was demonstrated through a probabilistic safety assessment of the conceptual repository for illustrative purposes. Through this study, it was shown that insufficient observed data could enhance the belief of prior distributions for input parameter values commonly available, which are usually uncertain. This is particularly applicable for nuclide behavior in and around the repository system, which typically exhibited a long time span and wide modeling domain.

• Economic and Environmental Geology
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• v.47 no.2
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• pp.169-180
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• 2014

Surface geological and trench surveys and drilling exploration (total length, 1,100 m; 9 drill holes) were carried out to secure new Au ore bodies in the area($0.96km^2$) of Actosity gold field, where is located at the western Kuldjuktau mineralized district in the middle territory of Uzbekistan. Several Au ore bodies occurring as tabular or lens shapes with thickness of 0.5~35 m were newly discovered on the outcrops and extended to $N40{\sim}70^{\circ}\;W$ direction with dipping of $70{\sim}90^{\circ}$ SW or NE. Indicated ore resource of gold with Au grade of 0.25~3.52 mg/kg was newly estimated by 2,382 t(gold resource of 2.5 t) as a result of 9 drilling exploration in 2010~2012 from the Actosity gold field. Judging from the ore resources and Au grade of the Actosity gold field, economic potentiality of mining development seems to be low. Because of high possibility to secure new ore resources through more detailed exploration works from the Actosity area, the growth of econonic value will be expected by a mine of middle scale.

• Economic and Environmental Geology
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• v.3 no.3
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• pp.169-176
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• 1970

Kubong Gold Mine is located in Kuryongri, Sayang-myun, Chungyang-gun, Choongchung-Namdo.(latitude $36^{\circ}24^{\prime}N$. longitude $126^{\circ}45^{\prime}30^{{\prime}{\prime}}E$) The mine was begun to work soon after the inhabitants of this village had accidently discovered the outcrops in April 1908. It is one of the largest gold mines in Korea which produces 4,500 tons of crude ore a month. The geology in the area consists of granitic gneiss, banded gneiss, augen-gneiss, mica schist, limesilicate of Pre-Cambrian series and sedimentary rocks(sandstones & conglomerates) of Daedong series. Basic dikes intrude the former formations. The country rock of the ore deposit is a group of the metamorphic rocks mentioned above. Gold-silver bearing quartz vein contains small amounts of pyrite, chalcopyrite, arsenopyrite, galena and sphalerite in which gold and silver occur as native state. The vein strikes $N30^{\circ}{\sim}60^{\circ}E$ and dips $20^{\circ}{\sim}50^{\circ}S$ and the average width of the vein is estimated 1 to 1.5m. Average grade of ore is Au:6~8gr/t and Ag:5~6gr/t. The ore shoot continues from the outcrop to the depth of -1760ML with dip of $20{\sim}25^{\circ}$ and strike extension reaches to 400m at the depth of -1440 ML and to more or less 200m at below. Highgrade of ore vein was found at the lowest level of the ore shoot at the time of recent field survey at the end of August 1970. Its average grade was estimated as Au:20gr/t and its width 1~2.5M in average. A series of futher prospecting for other new ore shoot or parallel veins are urgent and crosscut prospecting along the horizontal level is strongly recommended.

• Journal of Technologic Dentistry
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• v.28 no.1
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• pp.27-41
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• 2006

The physical property and phase transformation in a commercial dental casting high gold alloy was investigated as a function of ageing temperature and time using microvickers hardness tester, X-ray diffraction, optical and electron microscopy and EPMA analyser. 1. With increasing ageing time, the hardness of solution-treated gold alloys increased slowly at the initial stage of ageing treatment at an ageing temperature of $300{\sim}400^{\circ}C$, and it reached a maximum value of hardness at the medium stage. Finally, it decreased gradually during further ageing. The maximum value of hardness at was similar with that of the conventional materials and suitable for using as the crown & bridge. 2. During isothermal ageing at a temperature range of $300{\sim}400^{\circ}C$, three phases consisting of the Au-rich ${\alpha}_1$phase with a face-centered cubic structure, the Pt3Zn ${\alpha}_2$phase with an ordered AuCu3(L12) type(f.c.c.) and the Pt-rich ${\alpha}_3$phase with face-centered cubic structure in solution-treated gold alloys were transformed into different three phases consisting of the ${\alpha}_1$phase, the ${\alpha}_3$phase and the PtZn $\beta$phase with an ordered AuCu I(L10) type. 3. The hardening of gold alloys was attributed to the lattice strains of the matrix resulting from the transformation of the ${\alpha}_2$phase to the $\beta$phase. 4. The softening of gold alloys during over-ageing was attributed to the coarsening of the nodules consisting of the $\beta$phase and ${\alpha}_1$matrix.

• 한국문화재보존과학회:학술대회논문집
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• 2007.10a
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• pp.29-31
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• 2007