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Iron ore occurrence: usual chemical form in nature Considering common commercial iron ores, identify the chemical class in which iron is usually found. Choose the correct option.

Difficulty: Easy

Oxides
Carbonates
Sulphides
All of these

Correct Answer: Oxides

Explanation:

Concept

Commercial iron ores are predominantly oxides/hydroxides: haematite (Fe₂O₃), magnetite (Fe₃O₄), limonite/goethite (hydrated oxides).
Carbonate (siderite, FeCO₃) exists but is less common as a primary commercial ore; sulphides (e.g., pyrite) are not typical iron ores due to sulphur problems.

Final Answer
Oxides

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