sedimentary
Mudstone
Argillaceous sedimentary rock (dominated by clay and silt-sized particles)
AI-generated identification · may be incorrectHardness 2-3 on the Mohs scale, earthy dull luster, fine-grained texture, and uniform brown to reddish-brown coloration.
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Physical properties
Hardness 2-3 on the Mohs scale, earthy dull luster, fine-grained texture, and uniform brown to reddish-brown coloration.
Formation & geological history
Formed by the compaction and lithification of silt and clay minerals deposited in low-energy environments like lake beds, floodplains, or deep marine basins.
Uses & applications
Used primarily as raw material in the manufacture of Portland cement, bricks, and ceramics.
Geological facts
Mudstone constitutes more than 60% of all sedimentary rocks exposed on Earth's surface and frequently preserves trace fossils.
Field identification & locations
Identified in the field by its fine-grained, non-fissile earthy texture that easily scratches with a steel blade; found globally in sedimentary basins.
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