Question

Hydraulic washing is based on the differences in:

• A. special gravities of the ore and gangue particles
• B. special density of the ore and gangue particles
• C. special viscosity of the ore and gangue particles
• D. both $A$ and $B$

Answer 1

The correct option is A special gravities of the ore and gangue particles

Hydraulic washing is also known as gravity separation method.

It is based on gravity differences between the ore and the gangue particles. It involves the removal of unwanted metals and gangue to purify the ore. The ore is poured over a hydraulic classifier and jet of water is allowed to flow.

The denser ore settle in grooves and gangue is washed away. It is used for heavy oxide ores of lead, tin, iron etc.

Option A is correct.