Which of the following is not an ore of Iron

Options

A. limonite
B. cassiterite
C. magnetite
D. none of these .

Explanation

To determine which of the following is not an ore of iron, we will evaluate each option provided in the question.

1. **Limonite**:
- Limonite is an iron ore with the chemical formula FeOOH or can also be represented as Fe2O3·3H2O.
- The percentage of iron in limonite is approximately 59.8%.
- Therefore, limonite is indeed an ore of iron.

2. **Cassiterite**:
- Cassiterite is the primary ore of tin, with the chemical formula SnO2.
- Since it is an ore of tin and not iron, this indicates that cassiterite is not an ore of iron.

3. **Magnetite**:
- Magnetite is another ore of iron, with the chemical formula Fe3O4.
- The percentage of iron in magnetite is about 72.4%.
- Hence, magnetite is also an ore of iron.

4. **None of these**:
- This option suggests that all the mentioned minerals are ores of iron, which is incorrect since cassiterite is not.

Based on the evaluations above, the option that is not an ore of iron is **Cassiterite**.

**Final Answer**: Cassiterite is not an ore of iron.

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