sedimentary
Anthracite Coal
Anthracite
AI-generated identification · may be incorrectMohs hardness 2.5-3, black to dark grey, sub-metallic vitreous luster, conchoidal fracture, lacks visible crystal structure, specific gravity 1.3-1.8
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Physical properties
Mohs hardness 2.5-3, black to dark grey, sub-metallic vitreous luster, conchoidal fracture, lacks visible crystal structure, specific gravity 1.3-1.8
Formation & geological history
High-grade metamorphic-like sedimentary rock formed from deeply buried plant matter under extreme pressure and heat over millions of years (Carboniferous era).
Uses & applications
Clean-burning fuel for heating, industrial filter media for water purification, and historically as a domestic fuel source.
Geological facts
Anthracite has the highest carbon content of all coal types (86% to 97%). It is often referred to as 'hard coal' and burns with a short blue flame and little smoke.
Field identification & locations
Identified by its shiny, almost metallic jet-black appearance and conchoidal (shell-like) fracture. Commonly found in the Appalachian region of Pennsylvania, USA.
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