Anthracite Coal

Physical Properties

Hardness: 2.7-3.0 on Mohs scale; Color: Jet black to brownish-black; Luster: Submetallic, vitreous, or dull; Structure: Amorphous (non-crystalline); Cleavage: None/Conchoidal fracture; Specific Gravity: 1.3-1.4

Formation & Geological History

Formed through the regional metamorphism of bituminous coal under intense pressure and heat. This process (coalification) typically takes millions of years, often occurring in folded mountain belts like the Appalachians.

Uses & Applications

Primarily used as a residential and industrial fuel due to its high energy density and low smoke production. Also used in water filtration systems and as a source of carbon in steelmaking.

Geological Facts

Anthracite is the highest rank of coal, containing between 86% and 97% carbon. It is often referred to as 'hard coal' and burns with a short, blue, and smokeless flame.

Field Identification & Locations

Identify by its distinctly shiny, metallic-looking surface and smooth conchoidal (shell-like) fracture patterns. It does not leave soot on the hands like lower-grade coals. Commonly found in Pennsylvania, USA, and South Wales, UK.

Identified on: 4/14/2026

Mode: Standard