Which does not contain aluminium ?

Options

A. Bauxite
B. Corundum
C. Diaspore
D. Dolomite

Explanation

To determine which of the given options does not contain aluminum, we will analyze each option based on its chemical composition.

### Step-by-Step Solution:

1. **Identify the Options**: We have four options to consider:
- A) Bauxite
- B) Corundum
- C) Diaspore
- D) Dolomite

2. **Analyze Each Option**:
- **Option A: Bauxite**
- Chemical Formula: Al2O3·2H2O
- Contains aluminum (Al).
- Conclusion: This option cannot be the answer.

- **Option B: Corundum**
- Chemical Formula: Al2O3
- Contains aluminum (Al).
- Conclusion: This option cannot be the answer.

- **Option C: Diaspore**
- Chemical Formula: Al2O3·H2O
- Contains aluminum (Al).
- Conclusion: This option cannot be the answer.

- **Option D: Dolomite**
- Chemical Formula: CaCO3·MgCO3
- Does not contain aluminum (Al).
- Conclusion: This option is the answer.

3. **Final Conclusion**: The mineral that does not contain aluminum is **Dolomite** (Option D).

### Answer:
**D) Dolomite**

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