Conglomerate

LL Demos & Labs: Rock Profile: Conglomerate, Lab: Conglomerate Stew

This specimen looks like a piece of leftover, discarded concrete. That is why geologists describe conglomerate as “nature’s concrete.” When you have a fast moving, turbulent river or a near-shore marine deposit where the waves and incoming water are always mixing, you get conglomerate. This is a clastic sedimentary rock that is composed of particles of sediment, gravel and rocks of all sizes that have been cemented together with minerals.