• Economic and Environmental Geology
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• v.7 no.2
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• pp.45-62
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• 1974

Scheelite deposits in Sangdong mine are divided into three parallel vein groups, namely "Hanging-wall vein" which is located in the lowest parts of Pungchon Limestone, "Main vein" the most productive vein replaced a intercalated limestone bed in Myobong slate, "Foot-wall veins" a group of several thin veins parallel to main vein in Myobong slate. Besides the above, there are many productive quartz veins imbedded in the above veins and Myobong slate. Molybdenite and wolframite are barren in the former three veins group but associates only in quartz veins. Both main vein and foot-wall veins show regular zonal distribution, quartz rich zone in the center, hornblende rich zone surrounding the quartz rich zone and diopside rich zone in the further outside to the marginal parts of the vein. According to the distribution of three main minerals, quartz, hornblende and diopside the main vein can be divided into three zones which are in turn grouped into 7 subzones by distinct mineral paragenesis. They are summerized as follows: A. Diopside rich zone: 1. garnet-diopside.fl.uorite subzone 2. diopside-zoisite-quartz subzone 3. diopside-plagioclase subzone B. Hornblende rich zone: 4. hornblende-diopside-quartz subzone 5. hornblende-quartz-chlorite subzone 6. hornblende-plagioclase-quartz.sphene subzone C. Quartz rich zone: 7. quartz-mica-chlorite subzone The foot-wall veins can similarly be divided by mineral paragenesis into 3 zones, 6 subzones as follows: A. diopside rich zone: 1. garnet-diopside-quartz.fl.uorite subzone 2. garnet-diopside-wollastonite subzone B. Hornblende rich zone: 3. quartz-hornblende-chlorite subzone 4. hornblende-plagioclase-quartz subzone 5. hornblende-diopside-quartz subzone C. Quartz rich zone: 6. quartz-mica subzone The hanging-wall vein is generally grouped into 9 subzones by the mineral paragenesis which show random distribution. They are as follows: 1. diopside-garnet-fluorite subzone 2. diopside-zoisite-quartz subzone 3. diopside-hornblende-quartz-fluorite subzone 4. wollastonite-garnet-diopside subzone 5. hornblende-chlorite-quartz subzone 6. quartz-plagioclase-hornblende-sphene subzone 7. quartz-biotite subzone 8. quartz-calcite subzone 9. calcite-altered minerals subzone Among many composing minerals, garnet specially shows characteristic distribution and optical properties. Anisotropic and euhedral grossularite is generally distributed in the hanging wall vein and lower parts of the main vein, whereas isotropic and anhedral andradite in the upper parts of the main vein. Plagioclase (anorthite) and sphene are distributed ony near the foot-wall side of the aboveveins. wollastonite is a characteristic mineral in upper parts of the hang-wall vein. Molybdenite is distributed in the upper parts of quartz veins and wolframite in lower parts of quartz veins.

• Journal of the Korean Ceramic Society
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• v.15 no.4
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• pp.205-212
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• 1978

The hydration reaction of the slag-gypsum system was studied by X-ray diffraction, differential thermal analysis, optical icroscopic observation, and measurement of heat liberation of hydration. 1. Domestic granulated slag was almost noncrystalized state, and its mineral compositions calculated were 46.53% of gehlenite, 28.14% of akermanite, and 19.04% of wollastonite. 2. The slag quenched with water at relatively high temperature had better reactivity. 3. The production of ettringite, CSH gel and AH3 gel were stimulated by effect of $Ca(OH)_2$, $Mg(OH)_2$ and calcined dolomite as activators, and the strength of hardened body would be developed by forming compacted microstructure.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.3
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• pp.157-162
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• 1981

The studies we re carried out to examine the effect of soil improvement agents, such as lime, wollastonite and phosphate, in reducing the damage caused by hydrogen fluoride gas to the vegetative growth of rice. The yield loss, damage rate of the plant leaves, the fluoride of the plants were measured. The results obtained are summarized as follows : 1. The best results were obtained a treatment of lime and wollastonite. 2. The rice yield was not significantly increased by the soil improvement agents. 3. The fluoride content of the plants was positively correlated with yield loss and damage rate during vegetative growth.

• Journal of the Microelectronics and Packaging Society
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• v.6 no.1
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• pp.11-21
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• 1999

For microelectronic packaging application, the crystallizable glass powder in CaO-$A1_2O_3-SiO_2-B_2O_3$system was mixed with various amounts of alumina inclusions (\approx 4 $\mu \textrm{m}$), and its sintering behavior, crystallization behavior, and dielectric constant were examined in terms of vol% of alumina and the reaction between the alumina and the glass. Sintering of the CASB glass powder alone at $900^{\circ}C$ resulted in full densification (99.5%). Sintering of alumina-filled composite at $900^{\circ}C$ also resulted in a substantial denslfication higher than 97% of theoretical density, In this case, the maximum volume percent of alumina should be less than 40%. XRD analysis revealed that there was a partial dissolution of alumina into the glass. This alumina dissolution, however, did not show the particle growth and shape accommodation. Therefore, the sintering of both the pure glans and the alumina-filled composite was mainly achieved by the viscous flow and the redistribution of the glass. Alumina dissolution accelerated the crystallization initiation time at $1000^{\circ}C$ and hindered the densification of the glass. Dielectric constants of both the alumina-filled glass and the glass-ceramic composites were increased with increasing alumina content and followed rule of mixture. In case of the glass-ceramic matrix composites showed relatively lower dielectric constant than the glass matrix composite. Furthermore, as alumina content increased, crystallization behavior of the glass was changed due to the reaction between the glass and the alumina. As alumina reacted with the glass matrix, the major crystallized phase was shifted from wollastonite to gehlenite. In this system, alumina dissolution strongly depended on the particle size: When the particle size of alumina was increased to 15 $\mu\textrm{m}$, no sign of dissolution was observed and the major crystallized phase was wollastonite.

• Journal of Technologic Dentistry
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• v.21 no.1
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• pp.5-14
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• 1999

Glass ceramics for dental crown prosthesis were prepared by crystallization of CaO-MgO-SiO2-$P_2O_5-TiO_2$ glasses. Their crystallization behaviors have been investigated as a function of heattreatment temperature, holding time and chemical composition in relation to mechinical properties. Crystallization peak temperatures were determined by differential thermal analysis(DTA). Crystalline phases and mircostructures of heat-treated sample were determined by the means of powder X-ray diffraction(XRD) and scanning electron microscopy(SEM). The final crystalline phase assemblages and the microstructures of the samples were found to be dependent on glass compositions, heattreatment temperature, and holding time. 1st crystallization peak temperature(TP), affected strongly by apatite, was found to be increased or decreased. From the experiment, the following results were obtained : 1. The crystallization peak temperature($T_P$) formed by apatite increased until adding up to 9wt% $TiO_2$ to base glass composition, then decreased above that. 2. Apatite($Ca_{10}P_6O_{25}$), whitlockite(${\beta}-3CaO-P_2O_5$), $\beta$-wollastonite($CaSiO_3$), magnesium tianate($MaTiO_3$) and diopside(CaO-MgO-$2SiO_2$) crystal phase were precipitated in MgO-CaO-$SiO_2-TiO_2-P_2O_5$ glass system containing 9wt% and 11wt% of $TiO_2$ 3. Vickers hardness of samples increased with increasing heat-treatment temperature and Vickers hardness of S415T9 samples heat-treated at 1075 was approxi-mately 813Kg $mm^{-2}$ as maximum value. 4. Vickers hardness of samples increased due to precipitation of apatite, whitlockite, $\beta$-wollastonite, magnesium titanate, and diopside crystal phases within glass matrix.

• Ceramist
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• v.7 no.1
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• pp.47-60
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• 2004

골 대체재에서 생체활성재라 함은 이 물질이 체내에 식립 되었을 때 표면에 사람의 뼈와 물리적, 화학적으로 매우 유사한 성질을 갖는 저결정성 탄산 아파타이트가 스스로 형성되어 이 층을 매개로 하여 섬유성 조직의 생성 없이 신생골과 직접적으로 결합하는 능력을 갖는 물질을 말한다. 이와 같은 생체활성 물질은 1970년대 초 Hench가 Na$_2$O-CaO-SiO$_2$-P$_2$O$\^$5/ 글래스계에서 처음으로 발견하였으며 이를 Bioglass$\^$ⓡ/라고 명명한데서부터 유래한다. 그 후 결정성 아파타이트가 함유된 결정화 글래스인 Ceravital$\^$ⓡ/, 고결정성 아파타이트, 아파타이트와 wollastonite 결정을 포함한 Cerabone$\^$ⓡ/, 아파타이트와 phlogophite를 함유한 Bioverit$\^$ⓡ/, MgO-CaO-SiO$_2$-P$_2$O$\^$5/ 글래스, CaO-SiO$_2$ 글래스, ${\beta}$-tricalcium phosphate, 천연 calcite 등의 다양한 세라믹 물질이 생체활성을 갖는 것으로 보고되었다.(중략)

• The Journal of the Petrological Society of Korea
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• v.5 no.1
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• pp.21-34
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• 1996

Contact-metamorphosed calc-silicate hornfels of the Hwanggangni formation adjacent to Daeyasan granite in Goesan are characterized by the mineral assemblages. tremolite-clinozoisite-alkali feldspar-calcite, diopside-grossular-vesuvianite, and wollastonite-diopside-phlogopite-grossular-vesuvianite, indicating low $X_{CO_2}$ condition during contact metamorphism. Two trends of fluid-rock interactions are recognized; combination of infiltration and buffering in the outer portion of the aureole and fluid-dominated behavior in the most part of the aureole. Modal abundance of diopside produced during metamorphism was measured in order to estimate fluid/rock ratios and permeabilities with the assumption that equivalent volume of fluids estimated from the fluid/rock ratios flow through the rock body. The calculated fluid/rock rations and permeabilities range from 0.6 to 9 and $10^{-19}$ to $10^{-17}$ meabilities in the calc-silicate hosted contact aureoles and expected values during progressive metamorphism by theories.

• Economic and Environmental Geology
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• v.16 no.1
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• pp.37-49
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• 1983

The skarn type tungsten deposits are developed in the contact aureole of Jurassic biotite-hornblende granodiorite and limestone beds. The latter can be divided into the Great Limestone Series of Joseon System and Gabsan Formation which is correlative to the Hongjeom Series of Pyeongahn System. The skarns are impregnated in the limestone, sandstone, schist and granodiorite, and showing zonal distribution. The five skarn zones are from fresh limestone inwards to wollastonite-skarn, clinopyroxene-skarn, clinopyroxene-garnet skarn, garnet skarn and vesuvianite skarn zone. The ore mineral, scheelite, disseminates in the clinopyroxene-garnet and vesuvianite skarn zone, and the size of the scheelite crystals in vesuvianite skarn zone is larger than in clinopyroxene- garnet skarn zone. According to the mineral paragenesis and the composition of skarn minerals, oxygen fugacity ($fo_2$) is low. Fluid inclusions in quartz comprise much $LCO_2$ and fluid inclusion studies revealed that the homogenization temperatures range $240-290^{\circ}C$.

• Economic and Environmental Geology
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• v.27 no.5
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• pp.423-440
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• 1994

The Samhwa iron ore deposit, which is of typical magnetite skarn type, is located in the Samhwadong area of Donghae city, Kangwon-do, Korea. Skarn minerals are mainly composed of garnet, clinopyroxene, vesuvianite, wollastonite and small amounts of epidote and quartz. The garnets are isotropic $(Ad_{92.82{\sim}98.37})$ or anisotropic andradite $(Ad_{45.30{\sim}75.85})$ and grossular $(Gr_{86.26{\sim}24.47})$, the clinopyroxenes are ferrosalite and salite, Homogenization temperature of gas rich two phase inclusions in garnet are $368{\sim}593^{\circ}C$, and salnities of polyphase inclusions in garnet have 33.9~68.4 equ. NaCl wt. %. Garnet grain often shows composional variation from its core to rim. In other words, Fe and Al contents in garnet vary inversely, which suggest that the variation depends upon $f_{o2}$ during skarn formation.

• Journal of the Korean Ceramic Society
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• v.11 no.4
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• pp.25-30
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• 1974

The mixture of quartz powder and slaked lime with plenty water was oscillated in an autoclave and treated hydrothermally under the pressure of 10 kg/$\textrm{cm}^2$ for 8 hours. The main mineral synthesized was confirmed 11$\AA$ tobermorite by the method of X-ray diffraction and selected area electron diffraction. Tobermorite was heat-treated at 40$0^{\circ}C$, 80$0^{\circ}C$ and 100$0^{\circ}C$ for investigation of transformation of morphology and structure. Electron micrographs showed the thin platy structure of synthetic tobermorite with a little of crumpled foil or fibrous semi-crystalline calcium silicate hydrates. No difference in structure was appeared under the temperature of 80$0^{\circ}C$ but tobermorite converted gradually into wollastonite at 800$^{\circ}$~85$0^{\circ}C$. On heating, moulded material from tobermorite hardly shrinks under 80$0^{\circ}C$.