Question

which soil is rich in iron compound

Answer 1

element on earth, mostly in the form of ferromagnesium silicates. Soils typically contain 1–5% total iron, or 20,000–100,000 lb/a in the plow layer. Most of the iron in soil is found in silicate minerals or iron oxides and hydroxides, forms that are not readily available for plant use.
Three oxygen compounds of iron are known: ferrous oxide, FeO; ferric oxide, Fe2O3; and ferrosoferric oxide, or ferroferric oxide, Fe3O4, which contains iron in both +2 and +3 oxidation states. Ferrous oxide is a greenish to black powder used primarily as a pigment for glasses.
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