sedimentary

Conglomerate

Conglomeratic Sandstone

Hardness: 6-7 (Mohs scale) if quartz-rich; Color: Tan, beige, brown; Luster: Dull/Earthy; Texture: Clastic with rounded fragments; Specific gravity: approx. 2.6-2.8

Hardness: 6-7 (Mohs scale) if quartz-rich
Color: Tan, beige, brown
Luster: Dull/Earthy

Identified July 6, 2026More sedimentary →

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Physical properties

Hardness: 6-7 (Mohs scale) if quartz-rich; Color: Tan, beige, brown; Luster: Dull/Earthy; Texture: Clastic with rounded fragments; Specific gravity: approx. 2.6-2.8

Formation & geological history

Formed by the lithification of rounded gravel and pebbles in high-energy environments like riverbeds or alluvial fans. The specimens often date from various geological periods depending on location.

Uses & applications

Used primarily in the construction industry as aggregate for concrete and road building. Occasionally used as a decorative building stone or landscaping rock.

Geological facts

Often called 'puddingstone' when the matrix and clasts have contrasting colors. It serves as a record of ancient water flow direction and energy levels in paleo-environments.

Field identification & locations

Identify by the presence of rounded pebbles cemented together in a finer-grained matrix. Commonly found along river banks, beaches, and in ancient sedimentary basins.