What is the composition of laterite soil?
Laterite soil is rich in aluminum and iron, formed in wet and hot tropical areas. Almost all laterites are rusty red due to the presence of iron oxides. It is prepared by the long-lasting and intensive weathering of the parent rock.
What is laterite mineral?
Typical laterite is porous and claylike. It contains the iron oxide minerals goethite, HFeO2; lepidocrocite, FeO(OH); and hematite, Fe2O3. It also contains titanium oxides and hydrated oxides of aluminum, the most common and abundant of which is gibbsite, Al2O3·3H2O.
How is nickel laterite formed?
Nickel laterites form where ultramafic rocks are exposed to tropical weather. Relatively high temperatures and rainfall cause the destruction of nickel-bearing minerals, olivine and serpentine and the leaching of silicon and magnesium.
Is laterite a mineral or rock?
The laterite is loose Fe-rich subsoil rock formed as a result of residual enrichment and precipitation of iron hydroxide and oxide minerals from iron-derived deeper in the profile. This horizon can be composed largely of pisolites, gravel-sized subspherical accretionary concentrations (Ridley, 2013).
How is the laterite soil formed?
The laterite soil is formed under conditions of high temperature and heavy rainfall with alternate wet and dry periods, which leads to leaching of soil, leaving only oxides of iron and aluminum. It lacks fertility due to a lower base-exchanging capacity and a lower content of nitrogen, phosphorus, and potassium.
What crops are grown in laterite soil?
Crops in Laterite – Lateritic Soils When manured and irrigated, some laterites are suitable for growing plantation crops like tea, coffee, rubber, cinchona, coconut, arecanut, etc.
Is laterite soil good for farming?
Crops in Laterite – Lateritic Soils Laterite soils lack fertility due to intensive leaching. When manured and irrigated, some laterites are suitable for growing plantation crops like tea, coffee, rubber, cinchona, coconut, arecanut, etc. In some areas, these soils support grazing grounds and scrub forests.
What is the process by which laterite soil is formed?
Laterite soil is formed by chemical weathering that causes leaching of the parent sedimentary rocks, which is known as ‘lateralization’.
How are laterite deposits formed?
The Ni-Co laterite deposits are formed from the chemical weathering of the ultramafic rocks that removes the most soluble elements (Mg, calcium (Ca), and silicon (Si)) and concentrates the least soluble elements (iron (Fe), Ni, manganese (Mn), Co, zinc, (Zn), yttrium (Y), chromium (Cr), aluminum (Al), titanium (Ti).
How is nickel extracted from its ore?
Nickel from lateritic ore is extracted trough extractive metallurgy. It is extracted from its ores trough a conventional roasting method which removes the moisture from the ore. Next the nickel oxide is removed by reduction furnace which also greatly reduces the chemical bound water.
How is laterite formed?
Laterites are formed from the leaching of parent sedimentary rocks (sandstones, clays, limestones); metamorphic rocks (schists, gneisses, migmatites); igneous rocks (granites, basalts, gabbros, peridotites); and mineralized proto-ores; which leaves the more insoluble ions, predominantly iron and aluminum.
How is laterite soil formed give the main characteristics of laterite soil?
The formation of the laterite soil – The laterite soil is formed by high temperatures and intense rainfall with alternate wet and dry periods, resulting in soil leaching and the removal of only iron and aluminum oxides. Some crops can be grown when the soils are manured and irrigated.
What are the different types of Ni-CO laterite?
With respect to known classifications, three mineralogical subtypes of Ni-Co laterite deposits (Fe oxide, Mg hydrous silicate, and clay silicate) are selected by the dominant Ni-bearing mineral assemblage and statistically tested.
How big are the deposits of nickel laterites?
Middle grade Ni deposits contain more than 1.5% Ni and high grade Ni deposits are greater than 1.8%. Nickel Laterites are composed of long tabular bodies, over several hundred meters, but only tens of meters deep. These deposits develop from the mechanical and chemical breakdown of high temperature igneous rocks known as ultramafic rocks.
What kind of rock is in the laterite profile?
The laterite profile consists of five zones upward, which include: unweathered country rock at the base, saprolite, smectite, limonite (known as the ferruginous zone at Murrin Murrin), and a cap of colluvium.
How is the Ni-CO laterite deposit database compiled?
The Ni-Co laterite deposits involved in our analysis are mostly well explored and are partially or entirely mined. These deposits contain reliable quantitative data on ore tonnages and Ni and Co grades. The database, containing 66 fields, was compiled using File Maker Pro 8 software exported to Excel and tab-delineated spreadsheets.