Clay is a form of soil made up of very small particles of aluminum silicate created by the weathering of rock. It is composed of minerals such as kaolinites or smectites, sometimes with small quantities of quartz, metal oxides, and organic matter.

How long have people used clay?

The oldest known ceramic artifact was handbuilt and is dated as early as 28,000 BCE.  

What is Handbuilding?

Handbuilding is a technique of ceramics where one forms clay with hands and simple tools instead of the

Guide to Handbuilding Pottery

Clay is a material rich in history and possibilities for art making, and handbuilding pottery is the oldest use of the medium. The Crucible’s Ceramics Department offers a unique place to learn the different handbuilding pottery techniques of pinching, coiling, and slab rolling. Once you have experience with a few basic techniques, you can make your own functional tableware, vessels, sculpture, installations, and mixed media—the possibilities in ceramics are endless.

What is Handbuilding?

Handbuilding is a ceramics technique that allows you to create forms with clay and your hands, without using a throwing wheel. Before ceramicists invented the wheel, handbuilding was the only way they could create functional and artistic ceramic forms. The oldest known ceramic artifact was handbuilt and is dated as early as 28,000 BCE. All you need to get started are your clay, your hands, and a few simple tools.

Pinching Pots

Pinch pots are a great first handbuilding technique to learn when you first begin to work with clay. Simply begin with a single ball of clay and shape it into a small pot using only your hands by pressing your thumb into the center of the ball. Hold and spin the ball in one hand while you press the walls out with your thumb. Pinch pots are a direct method for beginning to work with clay and getting familiar with the medium.

How does raw clay become a finished piece?

There is something special about making pottery. While you don’t get instant gratification while making a piece, each stage is unique unto itself. Which makes each stage in the long process fun and even more rewarding.

• Though underglaze and glaze can both be used to color a piece of pottery, I love the various applications you can get by using an underglaze.

• Adding water to an underglaze transforms it into a watercolor application.

• Opaque colors require 2-3 coats. Underglaze can go over or under a glaze.

• It can be fired with a clear glaze on top for a shiny or matte seal or left without a top glaze for a velvety natural look. Underglaze colors are true to what is in the bottle.

• Underglaze can be applied to greenware or bisque ware. It is easier to use underglaze for intricate designs and a light coat of underglaze on the bottom of a piece will NOT stick to a kiln shelf.  

• Glazes are essentially a glass layer on the pottery ware. A glaze consists of ground-up materials suspended in water, which is applied to the piece.

• When it is fired, the ingredients melt together to form a glass layer.

• Glazes require 2-3 coats and a ¼ inch clear trim must be left around the base of a piece to prevent the glaze from running onto the kiln shelf, where it will harden and stick.

• The color of the glaze in the bottle has nothing to do with the finished color.

• It is best to fire strips of various glaze colored tiles to see how the glazes react to the clay body you are using before applying it to a finished product.

What is Pottery?

Pottery is the process and the products of forming vessels and other objects with clay and other ceramic materials, which are fired at high temperatures to give them a hard and durable form.

Plastic Stage :

Out of the bag clay is about 30% water. It is very malleable (flexible), and you are able to create an endless variety of shapes.

 Shaping Stage:

The clay has stiffened a bit and can hold shapes and scoring for joining pieces. 

Drying Stage:

The molding is over, but the clay is too wet to add handles or decorate. Let it settle and dry to the next stage.

Leather Hard:

The clay feels like soft leather. The clay has stiffened up enough to be able to handle it without marking it up with your fingers. You can trim, attach, and decorate, but the ability to move the clay around is gone. If you try your clay will start to crack.  

Bone Dry:

All of the water has evaporated from the clay. It is very fragile at this stage and must be handled with care. This process can take at least a week or even longer, depending on the thickness of the piece and the climate you live in. Better safe than sorry, otherwise your piece may blow up in the kiln. Some of my pieces have taken 4 weeks to dry. Once completely dry, the piece is ready to bisque fire in the kiln.  

Bisque Fire:

The bisque stage is when the clay is fired in the kiln between Cone 08 (1728F) and Cone 04 (1945F) to remove any chemically bonded water and impurities from the clay. This causes the clay to change permanently making it much harder but still porous enough to absorb the glazes nicely.

Pre-Glaze:

There are several ways of glazing at this stage, but first, you have to prepare your bisque ware. The best way to prepare your bisque pieces for glazing is to remove any fingerprints, dirt, or dust. To do this rinse it under running water or wipe it down with a damp sponge. Then make sure your piece is dry before glazing.

This stage is where the magic happens. The glazes, underglazes, or other colorants you have applied melts into the pottery and vitrifies, creating beautiful colors and patterns. Waiting to see the results of the colorants you have applied is exciting.

The final fire can be done in different ways. If you are gas firing or electric firing the most important thing you need to know is temperature. My cone 5-6 clay is fired at mid-range in an electric kiln to around 2200 degrees Fahrenheit. When choosing your clay and glaze make sure it says cone 5-6, not 05 or 06. It’s important to be aware of the zero before the number. Zero Before a Number = Fire at Low Temperature.

Kaolin – A primary clay component of porcelain.

Kickwheel – A large turn table powered by kicking or an electric motor, designed to spin while shaping clay into various designs with one’s hands. Similar principle as a lathe.

Kiln – the oven used to fire or bake clay or glass items.

Kiln Sitter – the part of a kiln that holds the firing cones and gauges the temperature then automatically shuts off the kiln.