Coke is the solid remains after certain varieties of bituminous coals are burned to high temperatures in the absence of air until nearly all of the volatile elements have been driven off.
It is greyish-black in color
Important uses of coke:
Coke is most commonly used as a fuel for fires, furnaces, and blacksmithing.
It is used as a reducing agent in the extraction of metals. Example- Zinc and Iron, etc.
It is used in blast furnaces to produce iron from its ore.