According to the experts, there are three main types of ceramics, as determined by the composition of the material, and the type of firing used to make it. When you are choosing decorative ceramic tile for your home, you need to understand the difference between them, as they each have quite different properties and uses.
How are ceramics made?
Ceramics are derived from a mixture of natural substances, including clay and sand. Chemically, the compounds in these substances are complex silicates. It is the elements other than silicon and oxygen that determine the properties of the ceramics that are made from them. For example, the presence of iron in the silicate causes a red-orange color.
When the silicates are subjected to very high temperatures ( 900 to 1400°C ), the water present in the original compounds is driven out, allowing chemical bonding between the layers of the silicate. This gives the ceramic structural strength which the original material did not have.
What are the three types of ceramic tile?
Earthenware is porous, opaque, and easily scratched. But it is a popular ceramic used by hobbyists to make pottery, since it is easy to form into bowls or vases. The firing process can be done in a home kiln, in which the temperature varies from 900°C ( red ) to 1100°C ( yellow-orange ). When not used for pots, it may be called quarry tile, or terracotta.
Stoneware is non-porous, and after firing it has a very smooth surface. It is difficult to scratch, so is used for cooking and tableware. And it is also the ceramic most commonly used for decorative ceramic tile.
Porcelain is also non-porous and has a smooth surface, but it is much harder than stoneware, and is glassier. This is caused by being fired at a much higher temperature ( 1200 to 1400°C ).
There are several terms that are often used incorrectly, and may cause confusion. Sometimes they are used to describe a type of ceramic tile, but they are really terms used to describe a characteristic or use of the tile.
Glazed tiles may be ceramic tiles of any type. The term "glazed" simply means that they are coated with glass-forming minerals that are glossy, and frequently colored. This process water-proofs the tiles, and makes them stain-resistant.
Mosaic tiles are not a different type of ceramic material. They are tiles that are usually small in size, so they can be used to make a "mosaic" - a decoration or picture. They can be made not only of ceramic material, but also of glass, natural stone, or even metal.
Ceramic tile can be used in the home in many ways, but that is not the topic of this article. Suffice it to say that now that you are familiar with the various types of ceramic, you should find it easier to choose decorative ceramic tile for whatever application you require.