Buying Clay For Pottery: Here Is What You Need To Know
If you are a new to pottery, it’s important to start out with the right pottery clay.
But to choose which clay is right for you, you first need to know what the different types of clay are and how to differentiate between them.
By the end of this article, you’ll know everything you need about clay to buy the right pottery clay!
What is clay?
Clay is made up of a mixture of sand, minerals, tiny rocks and other natural components, and it can come in different colors and textures depending on the mix. For instance, clays with a lot of iron oxide tend to have a reddish or orange hue, while those with little to no iron are usually gray or white.
Clay is a versatile material and has many uses. In the building industry, it’s used to make bricks, pipes, and walls. But today, we’re just going to focus on clay used for pottery making.
Properties of clay
There are many types of pottery clays, each with its own unique properties that make it suitable for certain projects. Here are some important properties to keep in mind when choosing your clay:
- Shrinkage: Just like us, clay shrinks as it dries, so keep in mind that your pieces will be slightly smaller once they go through the firing process. The shrinkage can range anywhere from 5% to 15%, depending on the type of clay you use.
- Absorption: This property refers to the amount of water a fired piece will absorb in relation to its weight. It ranges anywhere from 0% to 15%.
- Firing temperature or temperature range: The temperature at which your pieces need to be fired to reach maturity varies depending on both the type of clay and the size or thickness of your pieces.
- Plasticity: This property refers to how easy it is to manipulate the clay when it’s wet. The higher the plasticity, the more flexible and easy to work with the clay will be.
- Grog: Grog is fired clay that has been crushed into different particle sizes. It’s often added to clay to give it a unique texture and reduce shrinkage. You can either buy clay and grog separately and mix them yourself, or purchase clay that already has grog in it. Read this article for more information on grog.
My completed pottery ✨! Didn’t expect it to shrink so much 😅 https://t.co/K549PJH3BX pic.twitter.com/FVJ2FO0D3Q— Cheskeh (@cheskeh) April 20, 2021
Types of clay
There are three main types of clay you can choose from: stoneware, earthenware, and porcelain clay. Each one has its own unique characteristics and properties that make them more suitable for specific projects.
Starting with stoneware clay, this one is the most versatile and easiest to work with, especially if you’re just starting out. It comes in different colors and is great for making items of any size, whether on a pottery wheel or using handbuilding techniques. Once fired, pottery made from stoneware is strong, durable, and non-porous.
Earthenware clay is a bit thicker and heavier, but weaker than stoneware. Terracotta is a popular type of earthenware clay, known for its rich red color, and commonly used for tiles and flower pots. It only needs to be fired at a low temperature, but it is porous and needs to be glazed and fired a second time if you want it to hold liquids.
Porcelain clay is soft and flexible, but shaping it requires a lot of water and practice. It has the highest firing temperatures and requires a kiln to achieve the high heat needed. Porcelain pottery looks beautiful, but it might be better to wait until you have more experience before giving it a try.
How to make pottery clay
Making your own pottery clay at home is such a fun and easy process. All you need is soil, water, and a container. Simply mix the soil and water together and let it sit for a few minutes. This will allow the bigger rocks and sand to sink to the bottom, leaving you with a mixture of water and clay on top.
To make sure your clay is ready to use, simply filter the water using a fine cloth. And just like that, you’ll be left with smooth and wet clay that’s perfect for molding and shaping into your very own pottery creations. You can use the clay right away, or keep it in a sealed container.
Where to buy pottery clay
For smaller hobby-sized quantities, you can easily find what you need at an art supply store or online. Simply search for “pottery clay” and you’ll see a variety of options.
If you’re in need of larger quantities or specific types of clay, consider reaching out to a local supplier. Not only will it likely be more cost-effective than buying online, but you’ll also have the chance to talk to a clay expert who can help guide you in choosing the right type for your projects. Plus, you’ll be supporting a local business, which is always a win!
How to dry pottery clay
Pottery clay with automatically dry out when you leave it to dry in air. However, to completely remove all the water in the clay and make sure the clay transforms into ceramics, you’ll need to fire the clay at high temperatures in a kiln.
There are two main types of kilns, gas kilns and electric kilns. Gas kilns use natural gas or propane and give ceramics a unique and rustic look, but they can be more complicated to operate. On the other hand, electric kilns are the way to go for most people, especially beginners. They are easy to install, come in various sizes and prices to fit any budget, and are simple to operate.
A kiln is an essential piece of equipment for any home pottery studio.
However, a new kiln can be quite expensive. So when starting out, you can also reach out to a local pottery studio and see if you can use their kilns instead.
Can you bake pottery clay in a normal oven?
No, kitchen ovens just don’t reach the high temperatures needed to fire pottery properly. To get that heat, you’ll need a kiln designed specifically for firing ceramics.
Now, if you’re looking for a more DIY approach, you could try pit firing, but keep in mind that getting the temperature just right can be challenging.
So, if you want to ensure a successful firing and get the most out of your pottery clay, investing in a kiln would be the best bet.
I hoped this article has prepared you to buy the right type of pottery clay for the first time.
If you want to keep learning, you can also read these articles on the best pottery wheel and the best kiln to buy.