Experience from preparation and investigation of clay microstructure

摘要

Clays without expanding minerals can be preparedso that their microstructural constitution is preserved. Ifexpansive clays are treated in the same fashion there is an obviousrisk of very significant distortion of the particle arrangementbecause of drying, expansion and disintegration. It is also a riskthat impregnated clay becomes too soft to be cut for microscopy,but experience shows that embedding in a suitable plasticmonomer with subsequent polymerization gives sufficiently hardspecimens to make ultramicrotomy applicable. Impregnation withthis substance requires that the pore water is first removed, whichcan be done in several ways as described and discussed in thispaper. The thickness of the thin section should be as small aspossible for transmission electron microscopy, i.e.a few hundredangstroms, but thicker sections can be used for certainmicrostructural analysis.