What is the Difference Between Clay and Terracotta

The main difference between clay and terracotta is that clay has various colours ranging from white to grey to brown to deep red or orange while terracotta has a distinct red and orange hues.

Clay is an earthy material that contains fine particles of hydrous aluminium silicates and other minerals. Terracotta refers to a type of easily accessible earthenware clay that has rich red and orange hues, as well as, pottery or other items made using this clay.

Key Areas Covered

1. What is Clay
     – Definition, Properties, Uses
2. What is Terracotta
     – Definition, Properties, Uses
3. What is the Difference Between Clay and Terracotta
     – Comparison of Key Differences

Key Terms

Clay, Terracotta

What is Clay

Clay is a type of soil made up of tiny particles of hydrous aluminium silicate, which is created by weathering of rocks. Clay is the key ingredient in making pottery. Different forms of clay have varying degrees of plasticity. Plasticity is the ability to be stretched or bent. The more plastic a clay, more workable it is, i.e., easier to mould into different shapes. Depending on the soil content, clay can have different colours – from white to grey to brown to deep red or orange.

There are different types of clay with different properties. They have different uses according to their properties. Earthenware clay, stoneware clay and porcelain clay are three common types of clay in pottery.

Earthenware clay contains iron and other impurities, allowing it to reach optimum hardness at lower temperatures. This is porous, highly plastic, and easy to work with. Stoneware clay is typically grey in its raw form. It is usually fired at high temperatures, which changes its colour to a medium grey or brown. After firing, the clay becomes hard, dense, and stone-like. It is also non-porous and malleable.   Porcelain clay, on the other hand, is a versatile clay that can create functional household objects, decorative pieces, and fine art.

What is Terracotta

The word terracotta has several meanings or uses. Basically, this word originates from an Italian word that means, baked earth.  Terracotta can refer to a type of easily accessible clay that has rich red and orange hues. Terracotta also refers to pottery or other items made using organic clay fired in a potter’s kiln. Some people also use the word terracotta to describe any clay product that has a reddish-orange colour.

Terracotta clay can be found everywhere on earth and has a distinctly rich, red-orange colour. This colour is due to its iron content, which reacts with oxygen and results in different colours like orange, red, yellow and even pink. Therefore, terracotta is not pure clay. Moreover, terracotta is a porous clay to work with. It can be either glazed or unglazed. In addition, one coat of glaze can make it waterproof. Most importantly, terracotta is a type of earthenware.

As mentioned above, terracotta also refers to earthenware sculpture, clay vessels, water and wastewater pipes, roofing tiles, and bricks. It has a long history across the globe. Moreover, its use has been discovered in prehistoric art, as far back as 24,000 BC.

Difference Between Clay and Terracotta

Definition

Clay is an earthy material that contains fine particles of hydrous aluminium silicates and other minerals while terracotta refers to a type of easily accessible earthenware clay that has rich red and orange hues, as well as, pottery or other items made using this clay.

Type

Clay has different forms such as earthenware, stoneware, porcelain, and paper clay, while terracotta is a form of earthenware.

Colour

Clay can have different colours – from white to grey to brown to deep red or orange, depending on the soil content, while terracotta has a red-orange colour.

Conclusion

Clay is an earthy material that contains fine particles of hydrous aluminium silicates and other minerals while terracotta refers to a type of accessible earthenware clay that has rich red and orange hues, as well as, pottery or other items made using this clay. Clay can have different colours – from white to grey to brown to deep red or orange, depending on the soil content while terracotta has a red-orange colour. Thus, this is the main difference between clay and terracotta.

Reference:

1. D’Souza, Sara. “What Is Terracotta and How Do You Use It?” The Spruce Crafts, Available here. 
2. “Types of Clay – Ceramics.” BBC News, BBC, Available here.

Image Courtesy:

1. “Clay Hands Work Free Photo” (CC0) via Needpix.com
2. “Tiles Roofing Terracotta Free Photo” (CC0) via Needpix.com