SOLD BY: LATERITE
“Laterite can be described as a porous soil which ranging from soft earthly material to hard rock, and changes in colour from white to dark red, also depending on the quantity of iron in the soil. It is found below the earth surface and chemically made of silica and alumina, which is formed by the weathering of rocks hence given rise to many variation of laterite in composition and properties. Lateritic soil as a material has been used especially in the rural areas in Nigeria for many years to build houses. In order to modify the properties, the soil named “Laterite” was given by Buchanan (1807) in India from a Latin word “Later” meaning brick. He described the material as “subtle in great masses, without any sign of stratification, and is placed over the granite that forms the basis of Malayala (India).”Also Lacroix (1913) from his study, divided laterite into true laterite, silicate laterite, and lateritic clays on the basis of the hydroxides content; it was further developed by (Martin and Doyne, 1930) with the function of a silica-alumina ratio.”
Compositions, properties and classification laterite soils
Laterite can be possibly have high quantities of iron and silica apart from low aluminums contents, neither of these minerals are of high quantities enough for marketable extractions or use by industrialized.
Table 1, physical component of laterite.
| COMPONENT | % COMPOSITION |
| Gravel | 5 |
| Sand | 48 |
| Silt | 12 |
| Clay | 35 |
Source: Adepegba 1975
Chemical composition of Typical laterites Soils
| Location | Nigeria | Australia | Sudan |
| SiO2 | 26.5 | 3.5 | 34.92 |
| Al2O3 | 19.9 | 16.4 | 30.73 |
| Fe2O3 | 36.7 | 60.6 | 12.52 |
| FeO | – | – | – |
| MgO | – | – | 1.25 |
| CaO | – | – | 0.76 |
| Na2O | – | – | 0.90 |
| K2O | – | – | 0.60 |
| TiO2 | 1.1 | 1.3 | 1.02 |
| H2O | – | 10 | 1 |
SOURCE: Campbell (1977), Mohr and Van Baren (1954), Simpson (1991) cited by Yusuf, 2012.
Further research was done to classify and differentiate the difference between laterite found in Northern Nigeria and Western Malaysia, by pointing out that laterite in Western Malaysia, is of modular laterite which is most common where as in Northern Nigeria, laterite are known to overlie sandstone, granite gneiss, Mata sediments, limestone and alluvium occurs most frequently in the form of laterite crusts.”
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