One of the most known sedimentary rocks in the world is Limestone. It is a composition out of calcite one of the calcium carbonate minerals. It also need to form in shallow, soothed, warm and clear marine waters.

This type of environment is where organisms capable of forming calcium carbonate skeletons or shells can easily extract the needed ingredients from ocean water. commonly limestone is a biological sedimentary rock, formed out of the organic debris like accumulation of shell, coral, algal, fecal, and etc. After the animals die, the remain of their shell and skeletal debris accumulate as a sediment that have the potential to turn into limestone. also Their waste products can contribute to the sediment masses and help the process.

Another way of having limestone is by chemical sedimentary processes, like as the precipitation of calcium carbonate from lake or ocean waters meaning that they are formed by direct precipitation of calcium carbonate out of fresh waters. This type are chemical sedimentary rocks and they are less abundant and tougher than biological limestones. Most of the limestone-forming environments on earth are still active and can be found in shallow parts of the ocean. We can name some of these places like the Caribbean Sea, Indian Ocean, Persian Gulf, Gulf of Mexico, around Pacific Ocean islands, and within the Indonesian archipelago.

The other interesting way of having limestone is through evaporation. Stalactites, stalagmites, and other cave formations are examples of limestone that formed by evaporation. This is how, droplets of water should seep down from above the cave through fractures or in the cave ceiling. There they might evaporate before falling to the cave floor.

Many different types of limestone with their own name exists. These names are related to how these rocks are formed, their appearance, their composition, or even based on some of their physical properties. Chalk, Coquina, Crystalline Limestone, Dolomitic Limestone, Fossiliferous Limestone, Travertine are some of the more commonly encountered types of limestone.