Some Mineralogical and Physico-Chemical Properties of Fuller’s Earths from Tertiary Sediments in South Korea

慶尙道 地域의 三紀層中에 胚胎되어진 酸性白土는 主로 Ca-몽모리로나이트로 구성되며 이의 組成比는 95%까지에 이른다. 이에 수반되는 鑛物은 크리스토발라이트, 石英, 長石, 三井石鑛物 및 非結晶質이 있다. 示差熱分析, 적외선 및 전자현미경에 의한 이들의 기본적인 特性을 기재하였고 物理的性質을 涉性限界 및 양이온교환능을 측정기재하였다. 이들 資源의 이용가능한 용도범위를 고찰하였다.

Fuller’s earth deposits from Miocene sedimentary sequences in Gyeong Sang-do contain up to 95% Ca-montmorillonite accompanied by cristobalite, clinoptilolite, mordenite, quartz, feldspar and X-ray amorphous material. Differential thermal analysis, infrared and electron microscopic data are given for the montmorillonite component. The ease with which the exchangeable calcium of the montmorillonite could be replaced by sodium (to give a product with properties similar to that of a bentonite) was monitored by the Atterberg liquid limit test. Some samples tested as possible binders for foundry moulding sands gave results that compared favourably with material currently being used for this application. Many of the samples also met the OCMA specifications for clays used in drilling muds.