Limestone represents roughly 10 percent of all sedimentary rock in the world. Limestone generally forms on the shallow floors of tropical waters when seashells, sand and other sediment are compressed together. Limestone can be called a young marble. Crystals of cement grow around the young marble from grains that are made from animal seashells. A famous architectural marvel created with limestone is the Great Pyramid of Giza.
Special care needs to be taken when cleaning limestone because of its sensitivity and susceptibility to acid. This weakness can be seen in the dilapidation of some ancient structures built with limestone due to acid rain.
Although limestone is commonly used for building materials, it can also be used to make a number of other useful materials, such as lime, cement and even glass. In fact, limestone can be broken down into a powder to neutralize acid rain damage to lakes or patches of soil.
