• December 18, 2025
G-grade coal

This article examines the properties, distribution, economic role and industrial significance of a category frequently referred to as G-grade coal. The term can have several meanings depending on national standards…

  • December 8, 2025
Long-flame coal

Long-flame coal is a historically important and still widely used category of coal characterized by its distinctive burning behavior, broad occurrence in many coal basins, and versatile industrial applications. This…

  • December 6, 2025
Dry steam coal

This article explores the characteristics, occurrence, economic importance and industrial role of dry steam coal — a variety of coal primarily used for heat and power generation. Dry steam coal…

  • December 5, 2025
Fat coal

Fat coal — a traditional term used in many coal-producing countries — denotes a high-quality type of coal valued for its energy content and physical behavior during heating. Often associated…

  • December 2, 2025
Lignite

This article explores lignite — the lowest-rank form of coal often called “brown coal” — examining its geological origins, physical and chemical properties, where it occurs and is mined, its…

  • November 30, 2025
Low-volatile bituminous coal

Low-volatile bituminous coal is a high-rank coal grade prized for its elevated carbon content, strong coking properties and relatively low volatile matter. This article examines its geological characteristics, global distribution,…

  • November 29, 2025
Medium-volatile bituminous coal

Medium-volatile bituminous coal is a widely used and geologically important type of hard coal that sits in the mid-range of the coal rank scale. It combines relatively high fixed carbon…

  • November 29, 2025
High-volatile bituminous coal

High-volatile bituminous coal occupies an important place among the ranks of coal used around the world. This article summarizes its geological characteristics, where it occurs and is mined, economic and…

  • November 28, 2025
Bituminous coal

Bituminous coal is one of the most important and widely used ranks of coal worldwide. It occupies an intermediate position in the coalification scale between sub-bituminous coal and anthracite, combining…

  • November 24, 2025
Semi-anthracite

Semi-anthracite is a distinct rank of coal that occupies a middle ground between high-grade anthracite and the more common bituminous coals. It combines many of the advantageous physical and chemical…