sedimentary

Conglomerate

Conglomerate (Sedimentary Clastic Rock)

AI-generated identification · may be incorrect

Hardness: 2-7 (variable based on clasts/cement); Color: Brown, gray, or tan; Luster: Dull/Earthy; Crystal Structure: Amorphous clastic mass; Cleavage: None; Specific Gravity: 2.1-2.6

Hardness: 2-7 (variable based on clasts/cement)
Color: Brown, gray, or tan
Luster: Dull/Earthy

Identified June 28, 2026More sedimentary →

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Physical properties

Hardness: 2-7 (variable based on clasts/cement); Color: Brown, gray, or tan; Luster: Dull/Earthy; Crystal Structure: Amorphous clastic mass; Cleavage: None; Specific Gravity: 2.1-2.6

Formation & geological history

Formed through the lithification of rounded gravel and boulder-sized clasts in high-energy environments like riverbeds, alluvial fans, or beaches. Geological age ranges from Precambrian to Cenozoic.

Uses & applications

Used primarily as coarse aggregate in the construction industry and for ornamental stones or landscaping.

Geological facts

Conglomerate is often called "puddingstone" because the rounded rocks embedded in the finer matrix look like fruit in a pudding. It is a key indicator of ancient river systems.

Field identification & locations

Identify by looking for rounded pebbles or stones 'glued' together by a sandy or silty matrix. Found in sedimentary basins worldwide. Look for smooth, water-worn edges on internal rocks.