What is meant by blister copper? What is the reason for the formation of blister copper?

Explanation

### Step-by-Step Solution:

1. **Definition of Blister Copper**:
Blister copper is a form of copper that has a characteristic bubbly or blistered surface. This appearance is due to the presence of gas bubbles that form during the smelting process.

2. **Process of Formation**:
The formation of blister copper occurs during a process known as "besmeirization." This is a step in the extraction of copper from its ores, specifically during the smelting phase.

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