Think critically gangue is waste rock remaining after a mineral ore is removed. why is gangue sometimes reprocessed

Gangue is sometimes reprocessed for the purpose of obtaining extraminerals. This may be done using both the new and old methods in mining. Gangue refers to the worthless mined materials in ore, a common example of gangue is the small pieces of quartz in some ore. It is a waste rock or materials overlying an ore or mineral body that are displaced during mining without being processed or simply rock impurities.