Metallurgical coal is a special type of coal which can be used to produce metallurgical coke. There are two types of metallurgical coal: hard-coking coal and semi-soft coking coal. Cokes are mainly used in iron production. Biochar has a higher purity level than metallurgical cokes and is carbon neutral, so it burns at a higher temperature and has a low sulfur content. This means it is a superior fuel to metallurgical coke by far.