... detrital ones with quartz most common. They reflect the nature of the rocks of the nearest shore, but probably contain some admixture from more distant regions by wind transportation. The chemical precipitates are aragonite, CaCO 3 ; dolomite, 2 MgCO 3 · CaCO 3 ; parasepiolite (?), 2 MgO ·3 SiO 2 ·4 H 2 O...

... bases in the clay complex should be accurately investigated, and the exact mineralogical and chemical composition of the clay minerals and the questionable magnesium silicate, parasepiolite, should be determined. I feel that further progress will best be made by a colloidal chemist. An error...