Inertinite

Inertinite refers to a group of partially oxidized organic materials or fossilized charcoals, all sharing the characteristic that they typically are inert when heated in the absence of oxygen. Inertinite is a common maceral in most types of coal. The main inertinite submacerals are fusinite, semifusinite, micrinite, macrinite and funginite, with semifusinite being the most common. From the perspective of coal combustion, inertinite can be burned to yield heat, but does not yield significant volatile fractions during coking.

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