Read Table 7.3 to learn about chemical and biochemical sedimentary environments. Chemical and biochemical materials, once precipitated as solids, go through diagenesis just as clastic rocks do, though chemical changes are more important for these rocks than are physical changes. They are formed mostly in ocean waters, and mostly are biochemical. Coral reefs are also made from carbonate materials. The most important carbonate rock is limestone.
Common rocks formed are carbonates, rock salt, and gypsum.
Cherts Cherts are formed in the deep, deep ocean in some places.