sedimentary
Conglomerate (Greenstone/Pebble Conglomerate)
Polymictic Conglomerate
Hardness varies by component minerals (typically 6-7 overall), mixed color (green matrix with reddish-brown and dark rock clasts), dull to sub-vitreous luster, clastic texture composed of rounded to sub-rounded pebbles set in a finer-grained matrix.
Identified More sedimentary →
Explore Conglomerate (Greenstone/Pebble Conglomerate) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness varies by component minerals (typically 6-7 overall), mixed color (green matrix with reddish-brown and dark rock clasts), dull to sub-vitreous luster, clastic texture composed of rounded to sub-rounded pebbles set in a finer-grained matrix.
Formation & geological history
Formed by the consolidation and cementation of gravel-sized sediment, such as pebbles or boulders, often deposited by energetic streams, rivers, or marine coastal environments over millions of years.
Uses & applications
Used primarily in education, as decorative landscape stones, or collected as geological specimens.
Geological facts
Conglomerates provide direct evidence of past environmental conditions, indicating the presence of strong moving water capable of transporting large pebbles.
Field identification & locations
Easily identified in the field by its distinct 'plum pudding' appearance, featuring rounded rock fragments embedded in a contrasting matrix.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Fossiliferous Concretion
Septarian Concretion containing Brachiopods/Crinoids
fossil
Quartz pebble
Silicon dioxide (SiO2)
sedimentary
Sedimentary Sandstone
Arenite (Sedimentary Rock)
sedimentary
Generic Pebble / Rock Fragment
Lithic fragment / Weathered rock
sedimentary
Banded Siltstone / Mudstone Pebble
Siltstone / Argillite
sedimentary