sedimentary

Anthracite Coal

Anthracite (Carbon rank)

Hardness: 2.7-3.0 Mohs. Color: Jet black to dark steel-gray. Luster: Sub-metallic to vitreous (glassy). Fracture: Conchoidal. Specific gravity: 1.3-1.4. Low volatile content, high fixed carbon.

Hardness: 2
Color: Jet black to dark steel-gray
Luster: Sub-metallic to vitreous (glassy)

Identified July 22, 2026More sedimentary →

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Physical properties

Hardness: 2.7-3.0 Mohs. Color: Jet black to dark steel-gray. Luster: Sub-metallic to vitreous (glassy). Fracture: Conchoidal. Specific gravity: 1.3-1.4. Low volatile content, high fixed carbon.

Formation & geological history

Formed from accumulated swamp vegetation (peat) that underwent intense geological pressure and heat over hundreds of millions of years (often Carboniferous period), undergoing high-grade metamorphism of lower-grade coals.

Uses & applications

Historically used as a high-grade heating fuel due to its clean burn and high heat output. Today used in metallurgy, water filtration systems, power generation, and as carbon additives.

Geological facts

Anthracite is the highest rank of coal, containing 86% to 97% fixed carbon. Unlike softer bituminous coal, it burns with a clean, virtually smokeless blue flame.

Field identification & locations

Identified by its shiny, glassy black appearance, light weight relative to appearance, and clean handling compared to soft coal. Widely found in northeastern Pennsylvania, USA, as well as parts of China and Russia.