What should you look out for as a beginner?
Try not to get overwhelmed by the huge variety of clay in the pottery supply store. Admittedly, with terms like grog, effect clay, porcelain and stoneware, it’s easy to lose your way as a beginner. Not to worry: we will be your guide in the world of clay. We’ll get you ready to get wedging, handbuilding or throwing in no time!
The properties of clay
Every type of clay has its own properties. These properties largely determine how your finished piece will end up looking. They also affect the durability and watertightness of your creation. They determine how workable a type of clay is. Below we’ve summarised all of the properties you need to take into account when buying clay.
Above all, remember this: your choice of clay depends on what you personally like, what you want to do and whether you’re planning to use a potter’s wheel or not. By experimenting, you will find out which clay suits you best.
Plasticity
Plasticity has to do with the softness and workability of the clay. A plastic clay is rather soft, easy to work with and it retains its shape easily. If you choose a less plastic clay, it means you have to work harder to shape the clay. So as a beginner, it’s better to choose a plastic clay.
Durability
The durability determines how much weight your piece can withstand. Especially if you are making a larger piece, the strength of the clay is important. Using clay that is too weak for a large piece will cause your work to collapse.
Some types of clay contain grog. These are clay particles that have been fired and ground up. The more grog it contains, the stronger the clay and the less shrinkage you will get.
Water absorption
In general, clay contains around 20% water. This moisture starts to dissipate as soon as the clay comes into contact with the air. To keep the clay damp and workable, add water regularly. And know that some types of clay require more water than others.
Texture
Some types of clay have a rough texture, while others are more smooth. Clay with a lot of, or very coarse grog is much rougher than a clay with fine grog or no grog at all.
The choice depends on what you want to make and whether you’re planning to use a potter’s wheel or not. For wheel throwing it’s best to choose a clay with fine grog, otherwise the clay will chafe too much on your hands while throwing.
Want to know exactly how much your clay will shrink? Download our shrinkage ruler.
Three clay categories
In the pottery supply store, you will generally find three categories of clay: earthenware, stoneware and porcelain. What category you should choose, depends on what you are planning to make. These categories each have different properties.
Earthenware
Stoneware
Porcelain
Plasticity
Quite plastic
Plastic
Less plastic
Durability
Not strong
Strong
Very strong, but quickly distorts or cracks in the kiln
Water absorption
Permeable to water
Doesn’t need much water
Needs a lot of water
Texture
Determined by the grog added
Determined by the grog added
Few impurities
For beginners?
Yes
Yes
No
Are you not sure which clay to choose for your first or next project? Then choose earthenware or stoneware. These are two simple types of clay that are ideal for beginners.
What does the label say?
Usually a clay label will tell you:
- The type of clay
- Whether grog was added, and if so: how much and what texture of grog
- The colour of the clay after the first and second firing
- The firing temperature of the clay
Want to know more about clay?
Download our free beginner’s guide. Or get started with our pottery course for beginners and learn to throw a set of bowls, cups, dishes and cups in just a few weeks.
