State of the role of silica in the metallurgy of copper.

Explanation

### Step-by-Step Text Solution:

1. **Understanding the Role of Silica in Copper Metallurgy**:
- In the metallurgy of copper, silica (SiO2) plays a crucial role as a flux during the extraction process.

2. **Formation of Copper Sulfide**:
- The primary ore of copper is chalcopyrite (CuFeS2). When it is heated in the presence of oxygen, it undergoes a series of reactions to form copper(I) sulfide (Cu2S) and iron(II) sulfide (FeS):
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