sedimentary
Conglomerate
Conglomerate (clastic sedimentary rock)
Hardness: variable based on matrix (3-7 Mohs); Color: gray, brown, and tan; Luster: dull/earthy; Texture: coarse-grained with rounded clasts; Cleavage: none.
- Hardness
- variable based on matrix (3-7 Mohs)
- Color
- gray, brown, and tan
- Luster
- dull/earthy
Identified More sedimentary →
Explore Conglomerate in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: variable based on matrix (3-7 Mohs); Color: gray, brown, and tan; Luster: dull/earthy; Texture: coarse-grained with rounded clasts; Cleavage: none.
Formation & geological history
Formed through the deposition and subsequent lithification of rounded sediment particles larger than 2mm, typically in high-energy environments like riverbeds or alluvial fans.
Uses & applications
Used primarily in the construction industry as fill material, road base, or decorative stone in landscaping. Historically used for building stone.
Geological facts
Conglomerate is often called Nagelfluh in certain parts of Europe. It is the sedimentary equivalent of an 'old riverbed' frozen in time.
Field identification & locations
Identify in the field by looking for rounded pebbles or stones 'glued' together by a finer-grained matrix. It is very common in ancient river valleys and mountainous foothills.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Cone-in-cone structure (Limestone)
Cone-in-cone structure (Secondary Sedimentary Structure)
sedimentary
Sandstone Grain
Clastic Sedimentary Rock Grain (SiO2 dominated)
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary