sedimentary

Conglomerate

Hardness: variable (depends on clasts); Color: gray with varied clasts (white, brown, dark); Luster: dull to earthy matrix; Structure: clastic; Cleavage: none; SG: 2.5-2.8

Hardness: variable (depends on clasts)
Color: gray with varied clasts (white, brown, dark)
Luster: dull to earthy matrix

Identified June 25, 2026More sedimentary →

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Physical properties

Hardness: variable (depends on clasts); Color: gray with varied clasts (white, brown, dark); Luster: dull to earthy matrix; Structure: clastic; Cleavage: none; SG: 2.5-2.8

Formation & geological history

Formed in high-energy environments like riverbeds or alluvial fans where water carries large pebbles and cements them together with smaller sediment and mineral 'glue' over millions of years.

Uses & applications

Used primarily as construction aggregate, road fill, and sometimes as a decorative building stone. Fine specimens are used for educational geological collections.

Geological facts

Often called 'puddingstone' due to the appearance of round pebbles in a batter-like matrix. It provides high evidence of ancient water flow paths.

Field identification & locations

Identify by looking for rounded rock fragments larger than 2mm bonded in a finer-grained matrix. Commonly found in stream beds and coastal sedimentary basins.