What is clay?
What is clay?
Is clay simply dirt? “Dirt” covers a lot of ground! (sorry about the pun)! There are different types of ‘dirt’: topsoil, subsoil, rocks and clay. Topsoil contains a lot of organic material, which makes it good for growing plants. Rocks include bedrock and boulders all the way down to fine sands.
Clay begins as hard igneous rocks (igneous rocks are formed from molten lava that has cooled). This ‘parent’ rock decomposes and is washed away by water. It is then transported to another location where it settles out. This settled out substance has extremely small clay particles. It is a heavy, damp, plastic material.
What makes clay so different is the water molecules that are bound to the clay molecules. The water molecules remain bound to the clay molecules even if it is dried and then made into a power. Dried clay can be re-wet and once again you will get clay. With the proper amount of water clay can be molded and will retain it’s shape. This quality is known as clay’s plasticity.
Clay is changed by heat. Heat is the only thing that will transform clay into a rock-like ceramic material that is hard and water proof. Once transformed by heat the ceramic material can never again be turned back into plastic, mold-able substance.
Why is the underside of handmade pottery unglazed? Why is the underside of handmade pottery unglazed? Typically pottery made in factories are completely glazed, while handmade studio pottery often has an unglazed bottom. Glaze begins as a fine power applied to the...
Where in the world did those words come from? Kiln is derived from the Middle English word Kilne, which is derived from an Old English worn cylene, meaning oven, which is itself from the Latin word culina meaning 'kitchen, cooking stove' (which is the root word for...
How to fire pottery in a potters kiln.