Abstract
The major purpose of this study is to obtain the data in connection to clay minerals contained in green sand. These minerals are not only generated in the residual clays formed by decomposition of the parent materials, but also they are transported ane deposited as sediments. Generally, these clay minerals are composed of hydrated halloysite, montmorillonite and kaolinite. But some samples contain sericite of minor quantity. However quantitative relation between these clay minerals is various, we can divied into clases as follows:
(1) those contain montmorillonite predominantly.
(2) those contain hydrated halloysite predominantly.
(3) those contain both minerals in various ratioes.
Generally speaking, kaolinite is minor accessory mineral. These differences depend on vavious geological factors.
