Copper pyrites are concentrated by

Options

A. electromagnetic method
B. gravity method
C. froth floatation process
D. all the above

Answer

To solve the question regarding the concentration of copper pyrites (CuFeS2), we will analyze the methods mentioned and determine which one is appropriate for this specific ore.

### Step-by-Step Solution:

1. **Identify the Ore**:
- Copper pyrites is chemically represented as CuFeS2. It is a sulfide ore containing copper, iron, and sulfur.

2. **Evaluate the Concentration Methods**:
- **Electromagnetic Method**: This method is primarily used for separating magnetic impurities from ores. Since copper pyrites does not contain magnetic impurities, this method is not suitable.
- **Gravity Method**: This method is used to separate materials based on their density. It is effective for removing light impurities. However, copper pyrites does not have significant light impurities, making this method ineffective as well.
- **Froth Flotation Method**: This method is specifically designed for the concentration of sulfide ores. It exploits the differences in the surface properties of the minerals. Since copper pyrites is a sulfide ore, this method is appropriate for its concentration.

3. **Conclusion**:
- The most suitable method for concentrating copper pyrites is the **Froth Flotation Method**, which is used for sulfide ores.

### Final Answer:
Copper pyrites are concentrated by the Froth Flotation Method.

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