• Journal of the Mineralogical Society of Korea
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• v.22 no.3
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• pp.261-277
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• 2009

This study is aimed to emphasize the significance of ore selection in lime manufacturing through the evaluation of applied-mineralogical impact factors of crude ores controlling calcination characteristics for some domestic limestones used currently for lime manufacturing. To do this work, systematic characterization and determination were carried out for the limestone ores and their calcination products in a fixed calcining condition (target temperature: $1000^{\circ}C$, retention time: 30 minutes, 2, 4, 10, 16 hours), and the results were correlated and discussed. Selected high-Ca limestones in this study are as much as > 98 wt%, but they are somewhat diverse in crystallinity, texture, and impurity composition. Synthesized quicklimes are varied depending on such a difference in ore characters. The Pungchon limestone has relatively very low calcination rate, and the limestones from the Gabsan formation and the Jeongseon formation exhibit good quality in calcination rate and decrepitation. Among these samples, the limestone ore from the Jeongseon formation is evaluated to be the best for crude ore in manufacturing of highly-reactive quicklime. In addition, it is characteristic that the Gabsan limestone comparative rich in Fe-bearing mineral such as pyrite and goethite is more conspicuous in sintering effect.

• Journal of the Mineralogical Society of Korea
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• v.17 no.4
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• pp.339-355
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• 2004

Locality of domestic high-Ca limestones can be divided into three districts, i.e., (1) the Jecheon-Danyang area, (2) the Samcheok-Taebaek-Jungsun area, and (3) the Uljin-Andong area, in accordance with their geologic background and type of the deposits. Except for some crystalline limestones from the Jecheon-Danyang area, domestic high-Ca limestones were mostly recrystallized and Ca-enriched by the effects of hydrothermal alteration and/or thermal metamorphism. The lime-stones can be also divided into crystalline limestone type, marble type, micro- and mega-crystalline calcite types on the basis of their composition, crystallinity, and mineral facies. An applied-mineralogical characterization of the high-Ca limestones was done through the systematic analyses and tests for the limestones. The high-Ca limestones from the area (1), which are megascopic ally close to the original limestone in lithology, display lower whiteness, higher contents of CaO (51 ～ 54 wt.%), low crystallinity, and fine-grained texture. Two typical hydrothermal types of the high-Ca limestones from the area (2), i.e., micro- (mostly 0.2～0.3 mm) and mega-crystalline (2～15 em) calcite types, have comparatively higher whiteness and rather variable CaO contents (50～55 wt.%) with exhibiting quite different crystallinity each other. The micro-crystalline calcite type is especially dominant in this area, and has comparatively uniform crystallinity and homogeneous composition. Compared to these limestones, the high-Ca limestones from the area (3) show remarkable differences in grade and quality according to their types of deposit and occurrence. Based on these mineral characters and chemical composition, a possible scheme for industrial uses of the domestic high-Ca limestones was suggested.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.4
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• pp.469-484
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• 2022

The Janggun Pb-Zn deposit has been known one of the four largest deposits (Yeonhwa, Shinyemi, Uljin) in South Korea. The geology of this deposit consists of Precambrian Weonnam formation, Yulri group, Paleozoic Jangsan formation, Dueumri formation, Janggum limestone formation, Dongsugok formation, Jaesan formation and Mesozoic Dongwhachi formation and Chungyang granite. This Pb-Zn deposit is hydrothermal replacement deposit in Paleozoic Janggum limestone formation. The wallrock alteration that is remarkably recognized with Pb-Zn mineralization at this deposit consists of mainly rhodochrositization and dolomitization with minor of pyritization, sericitization and chloritization. Wallrock alteration is divided into the five zones (Pb-Zn orebody -> rhodochrosite zone -> dolomite zone -> dolomitic limestone zone -> limestone or dolomitic marble) from orebody to wallrock. The white mica from wallrock alteration occurs as fine or medium aggregate associated with Ca-dolomite, Ferroan ankerite, sideroplesite, rutile, apatite, arsenopyrite, pyrite, sphalerite, galena, quartz, chlorite and calcite. The structural formular of white mica from wallrock alteration is (K_0.77-0.62Na_0.03-0.00Ca_0.03-0.00Ba_0.00Sr_0.01)_0.82-0.64(Al_1.72-1.48Mg_0.48-0.20Fe_0.04-0.01Mn_0.03-0.00Ti_0.01-0.00Cr_{0.00As0.01-0.00}Co_0.03-0.00Zn_0.03-0.00Pb_0.05-0.00Ni_0.01-0.00)_2.07-1.92 (Si_3.43-3.33Al_0.67-0.57)_4.00O₁₀(OH_1.94-1.80F_0.20-0.06)_2.00. It indicated that white mica from wallrock alteration has less K, Na and Ca, and more Si than theoretical dioctahedral micas. The white micas from wallrock alteration of Janggun Pb-Zn deposit, Yeonhwa 1 Pb-Zn deposit and Baekjeon Au-Ag deposit, and limestone of Gumoonso area correspond to muscovite and phengite and white mica from wallrock alteration of Dunjeon Au-Ag deposit corresponds to muscovite. Compositional variations in white mica from wallrock alteration of these deposits and limeston of Gumoonso area are caused by mainly phengitic or Tschermark substitution mechanism (Janggun Pb-Zn deposit), mainly phengitic or Tschermark substitution and partly illitic substitution mechanism (Yeonhwa 1 Pb-Zn deposit, Dunjeon Au-Ag deposit and Baekjeon Au-Ag deposit), and mainly phengitic or Tschermark substitution and partly illitic substitution or Na⁺ <-> K⁺ substitution mechanism (Gumoonso area).