By comparing the mineralogy of the parent rock with the mineralogy of coarse sands in the soil and analysing this mineralogy in the different soil horizons, in general, it is possible to reconstruct how these transformations have taken place.

Sometimes these transformations are due to typical edaphic processes. This is the case of the transformation of gypsum into basanite.
This transformation process often already started in the original material. This would be the case of transformations of biotite to chlorite and of feldspars to sericite. On other occasions, the transformation is totally developed within the initial material. This is the case of the replacement of calcite by haematite observed in soils developed on Triassic marls. In other cases, the transformation starts in the original material and then develops, changing the direction of the transformation, in the soil. These would be the cases of the transformations: