Question

Gangue have
A ) sand and soil
B ) silt
C ) gravel
D ) all of theses

Answer 1

Hint: The impurities present in the ore are called gangue. Gangue is undesirable or unwanted material.

Complete answer:
Gangue has no market value. It is waste rock or sand or soil. It is present along with minerals in the ore deposit from which the metal is to be extracted. Gangue is different from overburden and tailings. Overburden is the waste rock that is present above the ore deposit. Tailings are pieces of rocks from which valuable minerals are already stripped of by natural processes.
Of the given options, select the options that are present in ore and are unwanted.
> Ore contains minerals with metals. Extraction of metal from ore by mining is economical. Metal ores include oxides, sulphides and silicates.
> Mineral is an inorganic solid substance that is naturally occurring and contains metals. The extraction of metals from minerals is economically not feasible.
> Gravel is a loose aggregation of small water-worn or pounded stones, pebbles, rock fragments. Gravel is also present in gangue. Sand and small gravel are important for manufacturing concrete.
> Silt is granular material. It is also present in gangue. The particle size of silt is in between that of sand and clay.

Hence, the correct option is option D ) all of these.

Note: Gangue does not contain only one type of substance. It's a mixture of several substances.