People have used limestone in construction for thousands of years.

Ancient buildings like the Pyramids at Giza are made of limestone, as is the Colosseum in Rome.  But limestone has many other uses in our modern world that you probably are not aware of – like in your toothpaste!

Here is everything you ever wanted to know about ... LIMESTONE!

FAST FACTS

  • One of the most important uses of limestone is as an ingredient in cement.
  • Although the terms cement and concrete often are used interchangeably, cement is actually an ingredient of concrete. Cement comprises 10-15% of the concrete mix.
  • Portland Cement is the most common type of cement. Bricklayer Joseph Aspdin of Leeds, England first made portland cement early in the 19th century by burning powdered limestone and clay in his kitchen stove. Today, Portland cement is everywhere around us in our modern infrastructure.
  • The stalactites (hanging cylindrical structures from the roof) and stalagmites (cylindrical structures sticking up from the floor) in caves are made of limestone. When the water leaves the cave it leaves limestone behind, which leads to formation of these interesting structures. This process takes thousands of years.
  • There is rock in your toothpaste! Toothpaste usually contains powdered limestone which is used as an abrasive to clean off plaque.
  • Chalk is a type of limestone that contains mostly shells from marine animals.
  • During the 1700s, limestone was used for lithography, which is when pictures are drawn on stones and then copied to other stones.
  • Marble is a type of limestone. Limestone turns into marble when subjected to high amounts of pressure and heat.
  • The Nova Scotia legislature’s flooring is made of limestone and marble. The floors contain visible sea fossils because limestone forms at the bottom of the ocean over millions of years as shells and bones of marine organisms pile up. The process preserves the organisms into fossils.
  • The Greeks and Romans recognized limestone’s unique chemical properties and used it as a bleaching agent, an ingredient in medicinal tonics and a soil sweetener in agriculture.