Sedi Ment

Sediment Sediment is the word geologists use for loose pieces of minerals and rock. Of course, pieces of rock come in all sizes so we have developed a way to classify them. The chart on the left shows we use for each grain size. Most of the names are ones you already use; sand, boulders, and clay, for example. The illustrations of sand and pebbles are shown at their actual sizes. Unfortunately silt and clay are smaller than a single pixel on your computer screen, so they don't show up well here! Cobbles and boulders are another problem - they are too big to fit on your screen! Metric system chart