Which of the following is not the ore of aluminium?

Options

A. Bauxite
B. Cryolite
C. Kernite
D. Corundum

Answer

To determine which of the following options is not an ore of aluminum, we will analyze each option provided:

1. **Bauxite (Option A)**:
- Bauxite is the primary ore of aluminum. Its chemical formula is Al2O3·2H2O (aluminum oxide with water).
- Since it is a well-known source of aluminum, it cannot be the correct answer.

2. **Cryolite (Option B)**:
- Cryolite has the chemical formula Na3AlF6. It is used in the extraction of aluminum but is not a primary ore itself.
- Despite this, it is still associated with aluminum production, so it is not the correct answer.

3. **Carnite (Option C)**:
- Carnite has the chemical formula Na2B4O7·4H2O. This compound is actually an ore of boron, not aluminum.
- Therefore, this is a strong candidate for the answer we are looking for.

4. **Corundum (Option D)**:
- Corundum is an anhydrous form of aluminum oxide (Al2O3) and is also considered an ore of aluminum.
- Thus, it cannot be the answer we seek.

Based on the analysis above, the option that is not an ore of aluminum is **C: Carnite**.

### Summary:
- **Correct Answer**: C: Carnite