The ore mined from the earth contains some unwanted substances called gangue. Enrichment of ore is done by various methods depending upon the nature of the impurities. Hydraulic washing is the process based on the difference in densities of ore and gangue particles. Froth floatation method is used for ores with different wetting properties of ore and gangue particles. On adding sulphide ore in a mixture of oil and water, the sulphide particles are wetted by oil and gangue particles are wetted by water. On passing air in this mixture, sulphide ore particles form light oily froth and reach the surface whereas gangue particles settle down at the bottom. Few ores are enriched by chemical processes.
The process in which lighter earthy particles are removed by jet of water is called

Options

A. leaching
B. levigation
C. froth floatation
D. none of these.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of the process used to remove lighter earthy particles from ore using a jet of water. This process is essential in the enrichment of ore, which is the first step in metal extraction.

2. **Identifying the Process**: The process that fits this description is known as "hydraulic washing." This method relies on the difference in densities between the ore and the gangue (unwanted materials).

3. **Explaining Hydraulic Washing**: In hydraulic washing, a stream of water is used to wash away the lighter gangue particles. The heavier ore particles remain behind due to their greater density. This technique effectively separates the valuable ore from the lighter impurities.

4. **Conclusion**: Therefore, the process in which lighter earthy particles are removed by a jet of water is called hydraulic washing.

**Final Answer**: The process in which lighter earthy particles are removed by a jet of water is called hydraulic washing.

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