High-ash thermal coal
High-ash thermal coal is a widely used but often overlooked category of fossil fuel that plays a significant role in electricity generation and industry in many parts of the world.…
Low-ash metallurgical coal
This article examines low-ash metallurgical coal — a specialized class of coal that is central to traditional steelmaking and remains an economically strategic commodity worldwide. The text explains the coal’s…
High-density coal
This article explores the characteristics, occurrence, extraction, economic importance and industrial uses of high-density coal — a group of high-rank coals and coal products notable for their elevated fixed carbon,…
Low-density coal
Low-density coal represents a group of lower-rank coals—most commonly known as lignite and sub-bituminous coals—that are characterized by higher moisture content, greater porosity, lower carbon concentration and reduced energy density…
Porous coal
Porous coal is a variant of coal characterized by a pronounced internal network of voids and channels that significantly influence its physical, chemical and economic behavior. Unlike dense, massive coal,…
Dense coal
Dense coal occupies a special place among the variety of coal types because of its high material compactness, elevated fixed carbon and calorific value, and specific industrial applications. In this…
Shatter-prone coal
The phenomenon of coal that readily breaks into smaller pieces during extraction and handling — commonly referred to as shatter-prone coal — presents a set of geological, operational and economic…
Cleated coal
Cleated coal is not a separate type of fuel but a descriptive term used by geologists and mining engineers to refer to coal seams that contain a well-developed system of…
Fractured coal
The term fractured coal refers to coal seams that contain pervasive natural cracks, joints and cleats which greatly influence their mechanical behavior, permeability and economic value. Fracturing may be the…
Raw anthracite
Raw anthracite is one of the highest-ranking coals in terms of carbon content and energy density. It has been valued for centuries for its distinctive physical and chemical properties, and…
