Metallurgical coal
• (Also called “met” coal) is an important raw material used in the steel-making process, although very small amounts of coal (relative to the amount used for electricity) are needed. The coal used to make steel is heated without air in an oven at temperatures of as much as 2,060°F (1,125°F), until most of its volatile matter is released.
• During this process, it softens, then liquefies, and re-solidifies into a hard porous material called “coke”. Coke is a porous, carbon-rich material used to make steel. The coke is mixed with iron ore and limestone to make molten iron, which is then further treated and heated to make steel.