sedimentary

Concrete

Anthropogenic Conglomerate

Hardness: Variable (typically 3-7 Mohs); Color: Grey with multi-colored aggregate (pink, grey, black); Luster: Dull/Earthy; Structure: Granular matrix with embedded clasts; Cleavage: None

Hardness: Variable (typically 3-7 Mohs)
Color: Grey with multi-colored aggregate (pink, grey, black)
Luster: Dull/Earthy

Identified June 24, 2026More sedimentary →

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Physical properties

Hardness: Variable (typically 3-7 Mohs); Color: Grey with multi-colored aggregate (pink, grey, black); Luster: Dull/Earthy; Structure: Granular matrix with embedded clasts; Cleavage: None

Formation & geological history

Human-made material formed by mixing cement, water, and coarse aggregates (crushed rock like granite). Though anthropogenic, it mimics the lithification process of natural sedimentary conglomerates.

Uses & applications

Primary construction material used for roads, sidewalks, buildings, and infrastructure globally.

Geological facts

Concrete is the most widely used man-made material in existence. While it contains natural minerals, it is classified as a technofossil or anthropogenic rock.

Field identification & locations

Identified by its uniform grey matrix hosting angular or rounded rock chips. It is ubiquitous in urban environments like the Murmansk region where this was found.