Interest of the mineralogical study of coarse sands in soils

Carlos Dorronsoro

The purpose of this article is to highlight the interest that the mineralogy of the coarse sand fraction (2-0.2 mm) can have for soil studies, both for scientific objectives and for the points of view applied.
When coarse sand grains are isolated and concentrated from the rest of the soil, a much more complete analysis can be made, which, on the other hand, is faster and easier than if these grains are examined in a microscopic preparation of the entire soil.

This article provides a summary of the mineralogy found in the coarse sand fraction of about a hundred soils in Spain and its application is detailed in order to extend knowledge of the parent rock, to detect lithological discontinuities and buried palaeosols as well as of the mineral origin and the transformations suffered during weathering, as assessment indices of the degree of evolution of the soils and to assess their fertility.