• Journal of the Mineralogical Society of Korea
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• v.5 no.2
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• pp.102-108
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• 1992

The natural (Ca, Mg)-buserite has been identified from the manganese oxideores of the Janggun mine, Korea, which have been formed by supergene weathering of sedimentary-metamorphic rhodochrosite. It occurs together with rancieite forming one very fine-grained buserite-rancieite flake. This (Ca, Mg)-buserite-rancieite occurs as microcystalline flaky crystals. It precipitated around the fine-grained takanelite aggregate. Electron microprobe analyses give the formula ($Ca_{.08}Mg_{.07}Mn_{.05}^{2+})Mn_{.89}^{4+}O_2{\cdot}1.46H_2O$ for (Ca, Mg)-buserite. The dehydration experiments by relative humidity control and heating as well as rehydration experiment by relative humidity control show that (Ca, Mg)-buserite dehydrates completely at 90$^{\circ}C$ and rehydrates up to 27% of the original state. The dehydration at 26% RH (corresponding to heating to about 40$^{\circ}C$) is characterized by thedecrease in the decrease in the intensity of 9.86${\AA}$ peak with slight shifting to 9.60${\AA}$. It is due to the loss of weakly bound water molecules in the interlayer. The dehydration from 40$^{\circ}C$ to 90$^{\circ}C$ is characterized by the gradual shifting of 001 peak from 9.6${\AA}$ to 7.42${\AA}$. It is due to the loss of weakly bound water molecules in the interlayer.

• Journal of the Mineralogical Society of Korea
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• v.13 no.4
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• pp.205-220
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• 2000

북동태평양 C-C지역의 우리나라 광구에서 산출되는 망간단괴의 내부조직을 크게 주상조직 층상대, 첨상조직 층상대, 첨상조직 괴상대, 첨상조직 다공질대 및 괴상조직 괴상대로 구분하였다. 주상조직 층상대에서는 버나다이트(vernadite)가 가장 우세하게 산출되며, 첨상조직 층상대에서는 부서라이크(buserite)가 함께 산출된다. 첨상조직 괴상대는 부서라이트의 산출이 두드러지며, 부분적으로 토도로카이트(todorokite)가 수반된다. 첨상조직 다공질대는 첨상체 또는 구상체로 이루어지며 부분적으로 괴상조직으로 교대되는데 주로 토도로카이트와 부서라이트로 구성되어 있다. 괴상조직을 갖는 괴상대에서는 토도로카이트와 버네사이트(birnessite)가 부서라이트와 함께 산출된다. 각 조직대별로 미세조직을 이루는 엽리들에 대해 전자현미분석을 실시하였다. 엽리의 화학조성을 구성하는 요인은 상관계수 군집분석에 의해 Mn-K의 Mn군, Cu-Ni-Zn-Mg(Ca-Na)의 Cu-Ni-Mg군 Fe-Co-Ti(Ca-P)의 Fe군과 Si-Al의 Si군 등 네 개군으로 구분된다. 각 조직대는 세 개 또는 네 개의 군으로 구성되며 이들 각군은 단괴에서 산출되는 광물과 밀접한 관계를 가진다. Mn군은 토도로카이트, Cu-Ni-Mg군은 부서라이트, Fe군은 함코발트수산화철광물, 그리고 Si군은 규산염광물에서 주로 기인하는 것으로 생각된다. 엽리의 화학조성은 이들 광물의 조합과 구성광물의 화학조성에 따라 지배되고 한 조직대내에서도 여러종류의 조합을 보이는데 이는 각 조직대의 엽리들의 성인과 밀접한 관련이 있는 것으로 생각된다.

• Journal of the Mineralogical Society of Korea
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• v.18 no.4 s.46
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• pp.259-266
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• 2005

X-ray diffraction (XRD), Electron microprobe analyses (EPMA) and heating experiments were used for mineralogical characterization of natural buserites collected from the Janggun and Dongnam mines. They are closely associated with $7-{\AA}$ phase (usually rancieite) in manganese oxide ores of the supergene oxidation zones of manganese carbonate deposits. Electron microprobe analyses give the average formula $(Ca_{0.78}Mg_{0.64}Mn^{2+}\;_{0.45})Mn^{4+}\;_{8.03}O_{18}\cdot13.2H_{2}O\;and\;(Zn_{0.81}Ca_{0.77}Mg_{0.26})Mn^{4+}\;_{8.00}O_{18}\cdot10.9H_{2}O$ for buserite from the Janggun and the Dongnam mine, respectively. The basal reflection of buserite from the Janggun mine shifts continuously from $9.86\;{\AA}\;at\;40^{\circ}C\;to\;7.60\;{\AA}\;at\;90^{\circ}C$, but the buserite from the Dongnam mine shows tendency of decreasing intensity in the $9.67^{\circ}C$ peak and of increasing intensity in the $7.53\;{\AA}$ peak in the range of $40\∼90^{\circ}C$, showing no gradual shifting of peaks.

• Journal of the Mineralogical Society of Korea
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• v.2 no.2
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• pp.90-99
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• 1989

Manganese deposits ar the Dongnam mine occur as vein in the Pungchon limestone of Ordovician age. Manganese ore veins consist of the hydrothermal manganese carbonate ores in the deeper part and the supergene manganese oxide ores in the shallow part. Manganese carbonate ores consist mainly of rhodochrosite, with minor amount of proxmangite, garnet, calcite, quartz, pyrite, galena and sphalerite. Manganese oxide ores consist of rancieite, buserite, birnessite, vernadite, todorokite, pydrolusite, nsutite, hydrohetaerosite and goethite. Manganese oxide minerals were formed in the following sequences; 1) rhodochrosite ${\rightarrow}$ vernadite ${\rightarrow}$ birnessite ${\rightarrow}$ nsutite ${\rightarrow}$ pyrolusite, 2) pyroxmangite ${\rightarrow}$ birnessite, 3) Buserite ${\rightarrow}$ ransieite. Todorokite, buserite and hydrohetaerolite were precipitated from solution in the later stage. The natural analogue of synthetic buserite has been discovered from the mine. It has been disclosed that buserite transforms to rancicite by dehydration, and that distinction between buserite and todorokite is possible by X-ray diffraction studies combined with dehydration experiment. Minerals identified from the mine have been characterized using various methods including polarizing microscopy, X-ray diffraction, thermal analysis, infrared spectroscopy, X-ray diffraction, thermal analysis, infrared spectroscopy, elecrton microscopy and dehydration experiment.

• Journal of the Mineralogical Society of Korea
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• v.2 no.1
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• pp.1-7
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• 1989

The terrestrial Ca-buserite has been found from Dongnam mine, Korea. It occurs in close association with rancieite in the manganese oxide ores which were formed by supergene weathering of hydrothermal rhodochrosite in veins. A study on this mineral using X-ray diffraction, infrared, polarizing and electron microscopes and dehydration experiment shows that the natural cabuserite (10$\AA$ phase) is more or less unstable, transforming partly to rancieite (7.5 $\AA$ phase) in the natural environment, and upon heating, its 10 $\AA$ line shifts to 7.5$\AA$ at 70-9$0^{\circ}C$. The Ca-buserite is the hydrate of rancieite.

• Korean Journal of Mineralogy and Petrology
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• v.33 no.4
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• pp.427-437
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• 2020

Manganese nodules, which are evaluated as potential metal resources, have been found in the Arctic Ocean as well as in the abyssal plains of the Pacific and Indian Oceans. Manganese nodules exhibit strong variations in the morphology, internal texture, chemical composition and mineralogy as they grow. The relationship between the texture and chemical elemental composition during the growth process is well documented, but the mineral composition variation during the growth process is not. Because the manganese oxide minerals in nodules are fine-grained and poorly crystalline, quantitative analysis for the mineral composition is challenging for the bulk nodule sample. This study investigated the internal texture and Mn-oxide mineral composition of manganese nodules obtained from the East Siberian Sea. Semi-quantitative analysis was attempted for three main Mn-oxide minerals constituting the manganese nodules (i.e., todorokite, buserite and birnessite) using the peak area ratio of X-ray diffraction analysis graphs. In the East Siberian Sea manganese nodules, birnessite is more abundant than buserite or todorokite, and no correlation is found between the mineral composition and the internal texture. Instead a correlation is found between the relative content of todorokite and the lamellae depth. The todorokite content tends to increase from the surface to the core of the nodules, which can be attributed to a recrystallization process or difference in the growth rate within the nodule. This study shows that semi-quantitative analysis of manganese oxide minerals using the peak area ratio is useful in the mineralogical study of manganese nodules.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.4
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• pp.241-253
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• 2021

Manganese nodules have been found in the shallow water depth of the Arctic Ocean as well as in the abyssal plains of the Pacific and Indian Oceans, but detailed study for them were rarely investigated. Manganese nodules, collected from the East Siberian Sea through the Arctic Expedition using Araon ice braking vessel, have a high potential for Mn mineral resources because they have high Mn content with high Mn/Fe ratio. This study investigated the external form, size and weight, internal texture for the non-spherical manganese nodule, which has about 7 % of total nodule from the East Siberian Sea. This study also researched the relative Mn-oxide mineral composition using the peak area ratio of X-ray diffraction pattern and their chemical composition. All data obtained from non-spherical nodules were compared with the spherical ones. Ellipsoidal, platy and irregular types are common among 5 groups of non-spherical manganese nodule based on the external form, and major axis and weight have positive relationship. All non-spherical manganese nodules have core mainly composed of mud sediments. The average Mn oxide mineral contents in nodules are birnessite, buserite and todorokite in descending order. Although mineral composition does not show any correlation with the external form, kind of core or internal structure, todorokite and buserite contents tend to increase and birnessite content decrease from the surface to the core in the nodule. Non-spherical manganese nodules have higher Mn content and Mn/Fe ratio than those from the shallow water depth of the Arctic Sea and even in the deep-sea of the Pacific and Indian Ocean. Although non-spherical nodule is larger and heavier, and has lower Mn content and Mn/Fe ratio than spherical nodule, there are not any differences in mineral composition and internal structure between them. Almost all manganese nodules collected from the East Siberian Sea are attributed to diagenetic process, because they are higher than 5 in Mn/Fe ratio.

• Journal of the Mineralogical Society of Korea
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• v.30 no.4
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• pp.219-227
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• 2017

Manganese (Mn) nodules in the Arctic Sea have been founded in the Kara Sea and Barents Sea, but mineral and chemical compositions have been rarely investigated. In this study, mineralogical and geochemical characteristics of Mn nodules obtained during the Arctic Expedition ARA07C in northern East Siberian Sea were identified, and then genesis of Mn nodules were estimated by using these characteristics. Main manganese oxide minerals constituting the manganese nodule were buserite, birnessite, and vernadite. The Mn nodules generally represent radiated and massive texture, and the layered texture was developed restrictively. The radiated texture, main feature of the manganese nodule in the East Siberian Sea, is mainly composed of cuspate-globular microstructure. Compared with the Mn nodules in Pacific and Indian Oceans, Mn nodules of the East Siberian Sea are abundant in Mn, but Fe is too scarce. There was no difference in the chemical composition and microstructures between outer and inner part of nodule. Therefore, nodules are most likely to have only one genesis during their growth, and all of nodules indicate the diagenetic in $Mn-Fe-(Cu+Ni+Co){\times}10$ ternary diagram. It is considered that the manganese nodules in the East Siberian Sea are characterized by high Mn contents because manganese contents in the Arctic Ocean were mainly resulted from river or coastal erosion and most of them are trapped in the Arctic Ocean.

• Mineral and Industry
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• v.18 no.1
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• pp.1-17
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• 2005

국내의 납석 광상은 대부분 백악기의 화산암류들이 열수변질되어 형성된 광상으로서, 주로 전남 및 경남 지역에 밀집되어 분포한다. 납석은 지질 여건상 주로 경상분지 내에 국제적인 규모의 풍부한 부존자원이 있지만, 그 동안의 개발에 의해서 고품위 황석들은 상당히 채진된 상황이다. 현재 개발되고 있는 광체들은 몇 곳의 광산을 제외하고는 대부분 저품위 광상을 이루고 있기 때문에, 새로운 광체의 탐광이 이루어지지 않는다면 앞으로 고품위 광석에 관한 한 국내의 수요를 충당하기 어려운 상황에 이를 것으로 예견된다. 현재 국내에서 납석으로 개발되고 있는 광석의 상당수(대략 $40\%$ 정도)가 엄밀한 의미에서는 사실상 납석이 아닌 고령토나 견운모 광석인 것으로 밝혀졌다. 엽납석을 함유하는 정상적인 형태의 납석들은 그수반 점토광물상에 의거하여 (l) 엽납석질, (2) 딕카이트질. (3) 일라이트질 및 (4) 딕카이트-일라이트질 유형으로 구분될 수 있다. 고령토 광물로는 대부분 딕카이트가 수반되고 외국에서는 흔히 수반되는 것으로 알려져 있는 고령석은 거의 함유되지 않는 것이 특징이다. 석영은 납석에서 점토광물 못지않게 그 용도를 가름하는 주요 성분으로서 대부분의 광석 유형에서 수반되지만 특히 일라이트질 납석에서 흔히 그리고 보다 많이 수반되는 양상을 보인다. X-선회절 정랑분석법은 납석의 품위를 산정하는데 유력한 수단이 될 수 있다. 특히 납석 이외의 점토광물들의 조성, 특히 일라이트의 함유 정도는 납석의 용도별 품위와 품질을 가름하는 주요 사항이다. 화학분석에 의한 납석의 평가 방식은 특히 납석의 백색 도기류와 같은 각종 세라믹스 제조 용도에서의 품질 평가에 결정적인 단서를 제공하는 유력한 평가수단이다. 특히 착색유발 성분인 철분의 존재와 그 함량을 정하고 요업용도에서 중요한 $Al_3O_3$와 알칼리 성분 함량을 검증하는데 필수적인 평가 방법이다. 이외에 주사전자현미경 관찰을 통해서 납석의 주요 품질 기준이 되는 극미립상 엽납석의 결정형, 조직 및 미시적 산출상태를 보다 정밀하게 평가할 수 있는 방안을 제공한다. 현행 광업법상의 납석을 비롯한 관련 광종들의 광물분류 체계가 모호하게 설정되어 있고 관련 인허가 부서에서의 전문성 및 지도력 부족으로 관련 산업계에 심각한 비효율성과 오류가 야기되고 있는 실정이다. 이를 개선하기 위해서는 납석의 광석평가 방식이 그 품위와 품질 개념 하에서 응용광물학적으로 적용되어야 할 것이다.