Diamond is a:

Options

A. Metallic Mineral
B. Non-metallic mineral
C. Ore
D. All of these

Explanation

**Step-by-Step Solution:**

1. **Identify the substance in question**: The question asks about diamond.

2. **Determine the composition of diamond**: Diamond is made up of carbon atoms.

3. **Understand the term 'allotropes'**: Allotropes are different forms of the same element that have different structures and properties.

4. **Classify diamond**: Since diamond is a form of carbon, it is classified as an allotrope of carbon.

5. **Identify the nature of diamond**: Diamond is a non-metallic substance, despite its hardness and brilliance.

6. **Conclude the answer**: Therefore, diamond is an allotrope of carbon and is classified as a non-metal.

**Final Answer**: Diamond is an allotrope of carbon and is a non-metal.

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