Limestone is a type of sedimentary rock that has been used since the days of the ancients. In fact, the ancient Egyptians implemented limestone in their construction of the great pyramids and other ancient peoples used limestone to construct buildings, monuments, and parts of their infrastructure.
But the effective use of limestone did not die with those ancient peoples. Limestone continued to be used in construction processes throughout modern times and was even among the most popular building materials in use in the 19th and 20th centuries.
In fact, in Canada there is a town that is called Limestone City because almost all of its original buildings, built in the hay day of limestone use back in the 19th century, have some component of limestone built into their structure. And the trend of using limestone for building things and for use in construction has continued to the present day.
One can find cut limestone used for flooring, windowsills, stair treads, and facing stones in modern buildings around the world. Cut limestone is heavy and very expensive but can be very elegant and aesthetically pleasing because of the sedimentary process from which it was formed.
Like all sedimentary rocks, limestone forms when particles of other rocks, like small pebbles and sand, along with any number of other sedimentary elements, such as shells, dirt, and other minerals, combine together into layers. With time, these layers harden into rock and form sedimentary rocks.
Sedimentary rocks are classified as limestone rocks when they contain at least fifty percent calcium carbonate, or in other words, limestone rocks form when sediments that contain calcium carbonate combine to form a sedimentary rock. One of the principle reasons why limestone is widely used as a building material is because of its inclusion of differing rocks and minerals that have been enveloped in the sedimentary rock formation of the limestone.
This advantage can be seen in the principle use of limestone in today’s construction habits which is to crush up the limestone for use in roofing shingles. When mixed with tar, the crushed limestone provides one of the best weather resistant roofing materials available, due largely to the various other components that comprise the limestone.
photo credit: wallyg