Non-metals are not as hard as metals. Name one exception which shows hardness.

Explanation

**Step-by-Step Solution:**

1. **Understanding Non-Metals**: Non-metals are generally softer than metals. They do not exhibit the same level of hardness as metals do.

2. **Identifying an Exception**: However, there are exceptions among non-metals that can exhibit hardness. We need to identify one such non-metal.

3. **Considering Carbon**: One well-known non-metal is carbon. Carbon has different forms known as allotropes.

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