How does the conductivity vary in diamond and graphite?

Explanation

### Step-by-Step Solution:

1. **Understanding Allotropes**:
- Diamond and graphite are both allotropes of carbon, meaning they are different structural forms of the same element.

2. **Structure of Diamond**:
- In diamond, each carbon atom is covalently bonded to four other carbon atoms in a three-dimensional tetrahedral structure. This strong bonding creates a rigid lattice.

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