Which one of the following is not a method of concentration of metal ores ?

Options

A. Gravity separation
B. Froth floatation process
C. Electromagnetic separtion
D. Smelting

Explanation

To determine which one of the following is not a method of concentration of metal ores, we need to first understand what concentration of metal ores means and the common methods used for this process.

### Step-by-Step Solution:

1. **Understanding Concentration of Metal Ores**:
- Concentration of metal ores refers to the process of removing impurities from the ore to increase the percentage of the desired metal. This is an essential step before the extraction of metals.

2. **Common Methods of Concentration**:
- There are several methods used for the concentration of metal ores. Some of the commonly known methods include:
- **Gravity Separation**: This method uses the difference in density between the ore and the impurities to separate them.
- **Froth Flotation**: This technique involves adding chemicals to a slurry of ground ore, which causes the desired mineral to attach to air bubbles and float to the surface, where it can be collected.
- **Electromagnetic Separation**: This method uses magnetic properties to separate magnetic ores from non-magnetic impurities.

3. **Identifying the Incorrect Method**:
- Among the methods mentioned, we need to identify which one does not belong to the concentration of metal ores.
- **Melting Process**: This is not a method of concentration. Instead, it is a method used in the extraction of metals after concentration has already taken place. Melting involves heating the concentrated ore to convert it into a liquid form, allowing for the separation of metal from its oxide.

4. **Conclusion**:
- Therefore, the method that is not a method of concentration of metal ores is the **Melting Process**.

### Final Answer:
The method that is not a method of concentration of metal ores is **Melting Process**.

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