We shared in our "Why Concrete" blog post (read it here!) that the words concrete and cement are often used interchangeably to describe the smooth, grey, composite material we all know.
At Home Again Studios, what we actually use to create our favorite home décor pieces is cement—an ingredient of concrete. In its basic form, cement is broken down stone mixed with a liquid and then hardened.
The earliest known occurrence of cement dates back 12 million years, when a spontaneous combustion produced reactions between limestone and oil shale. This resulted in natural deposits of cement that would lead to the future creation of concrete.
For millennia, civilizations tested out various versions of limestone and cement. The Great Pyramids of Giza used around 500,000 tons of mortar that included sand and burned gypsum. And on Crete, the Minoans created structures by mixing a water with a type of clay and volcanic ash.
Early forms of cement were also used to construct Grecian tombs in 1000BC, and parts of China’s Great Wall in 700BC.
By the rise of the Roman Empire in 300BC, the use of concrete was widespread. It was used to create ramps, terraces and roads that eventually connected the whole empire. By pouring the mixture into molds, soon they were able to create bricks, vaults, domes and arches, forming the iconic aqueducts, buildings and bathhouses we know today.
Roman concrete continues to endure, withstanding thousands of years of weathering. The Pantheon, built 1,896 years ago, is still as sturdy as ever! After the fall of the empire in 476AD though, the Roman recipe for concrete was lost, until manuscripts were found in 1414.
After this, concrete went dark for a while. Even during the Middle Ages, when they used hydraulic cement in canals, fortresses and harbours, concrete technology edged backward. In fact, during the Renaissance, only one person has been touted with attempting to build with concrete.
That is, until modern cement was created.
In 1793, John Smeaton was commissioned to build a lighthouse on the Eddystone Rocks in Cornwall, England. Through his work, he created a method for hydraulic lime and ultimately rediscovered how to make cement. The Eddystone Lighthouse stood for almost 130 years, outlasting the rocks underneath.
This process was further refined in 1824 when Joseph Aspdin burned the mixture in a kiln until all the carbon dioxide was removed. The result was Portland Cement, the most popular cement used today.
For decades, cement underwent strength testing and experimentation. In 1849, French gardener Joseph Monier reinforced concrete with embedded metal (steel) to create garden pots and tubes. This eventually led to the first concrete-reinforced bride and the Hoover Dam!
Around the world, iconic buildings and landmarks—the Panama Canal, Sydney Opera House, and the Colosseum—are all made from concrete.
So, next time you walk on a sidewalk or light your favorite Home Again Studios candle in a concrete pot, take a moment to appreciate the centuries of engineering that came before us.