sedimentary

Conglomerate

Conglomerate (clastic sedimentary rock)

AI-generated identification · may be incorrect

Hardness: 6-7 (based on quartz content); Color: White, tan, brown, reddish; Luster: Vitreous to earthy; Crystal Structure: Amorphous clasts within a matrix; Cleavage: None; Specific Gravity: 2.6-2.9

Hardness: 6-7 (based on quartz content)
Color: White, tan, brown, reddish
Luster: Vitreous to earthy

Identified May 5, 2026More sedimentary →

Explore Conglomerate in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 6-7 (based on quartz content); Color: White, tan, brown, reddish; Luster: Vitreous to earthy; Crystal Structure: Amorphous clasts within a matrix; Cleavage: None; Specific Gravity: 2.6-2.9

Formation & geological history

Formed by the consolidation and lithification of rounded gravel and pebbles, usually in high-energy environments like riverbeds or alluvial fans. Can be any geological age from Precambrian to Cenozoic.

Uses & applications

Used primarily in the construction industry as coarse aggregate for concrete and roadbeds. Also used as decorative stone in landscaping or for architectural facades.

Geological facts

Conglomerate is often nicknamed puddingstone because it looks like raisins or nuts in a cake. It can serve as a reservoir rock for petroleum and natural gas due to its porosity.

Field identification & locations

Identify by looking for rounded clasts (pebbles) larger than 2mm embedded in a finer-grained matrix. Look for them in areas with ancient river deposits or coastal outcrops.