Ferralsols and other Soils of the Hot Regions - Major Soil Groups of the World - page 155

Figure 5.3 shows an example of cuirass.
Fig. 5.3 Outcropped ferrallitic cuirass (Petroplinthite of WRB), Senegal. Scale : Roger
Maignien, scientist of ORSTOM-IRD and author of a thesis on the subject (Maignien 1958).
Photo : author.
Figure 5.4 shows a thin section made from a ferrallitic cuirass with
residual kaolinite (Nahon 1976).
Quartz
Clay coating
Anisotropic
ferruginous
plasma
Opaque
ferruginous
plasma
0.20 mm
Fig. 5.4 Ty p ical micromorphological structure of the cuirass in a Ferralsol (Nahon 1976).
Quartz grains (specks), ferruginous concentrations (black and opaque) and abundant clay
coatings (dashed lines) around the voids (white) are seen. Gibbsite is not observed here.