Unit 1: Introduction to Clay

Lesson 1: The Basics of Clay

Ceramics anything made from clay

Greenware clay that hasn't been fired/heated

Clay is formed naturally. The movement of ice, water, wind, and tree roots break down rock into the minerals that form clay.

A key ingredient of clay comes from granite - feldspar.

Clay Structure

Clay is made of microscopic platelets. When clay is moist, these platelets easily slide back and forth. Moisture also helps these platelets stick together.

The ability to hold together while being shaped is called plasticity.

The Effect of Heat

Fire or heat stops the platelets from moving. The clay shape returns to its rock-like state, becoming permanent.

When clay is heated quickly, the water expands as it turns into steam. This rapid expansion is so powerful, that the clay will explode. Trapped air can also explode.

Therefore, when working with clay, you must allow it to become completely dry (bone dry) before heating it.

Ancient Clay

Clay has been used since ancient times.

Nomads (wandering people) began to settle down when they learned to make storage containers out of clay. They also learned to make some foods easier to eat by cooking them in ceramic dishes.

Ceramics weren't only functional (objects with a purpose). Excavations of ancient tombs revealed that early people also made ceramic figures & animals as companions for the dead.

Clay Preparation

Early potters dug clay out of the ground. This clay had a lot of impurities, like rocks and plant matter.

In order to get rid of these impurities, they would dry the clay, smash it up, and pick out the impurities by hand.

Once they removed the impurities, they rehydrated or slaked the clay to return it to a workable state.

Clay Preparation

Eventually, potters found an easier way to purify their clay. They would add water to the clay, turning it into slip (liquid clay).

They would pour the slip from one container to another.

This process, called decanting, causes the coarser materials to settle to the bottom, while the desired clay is poured off.

Clay Preparation

Another traditional way of purifying clay is levigation. In this process, clay is prepared as a slip and allowed to flow down a gradual slope.

At the end of the slope, there is a lip. This blocks larger particles, but allows the clay to pass through.

Lesson 2: Clay Properties

Plasticity clay is able to be formed into shapes; clay can be made stronger by adding sand, straw, grog (crushed fired ceramics) or paper pulp.

Moisture if clay is too moist, it becomes weak and cannot hold its shape. Clay dries when exposed to air. However, only when it is fired has all the moisture been forced out of the clay.

Texture clay can be rough or smooth, depending on what ingredients were added (grog, for example)

Shrinkage clay shrinks as it dries

Clay Properties

Aging improves the plasticity of clay.

Early potters passed down their supply of clay onto their children.

If the clay had been stored for a long time, it had to be wedged (by kneading it until it has a uniform consistency).

Clay Properties:
The Pros & Cons of Drying

Clay shrinks as it dries. If it shrinks too quickly, it will crack. Therefore, we control the drying rate by wrapping the clay in plastic.

As clay dries, it becomes more able to hold its form. When clay is leather-hard, pressure can be applied to the clay and it will not easily collapse.

Elements of Design

Shape a two-dimensional image, like the typing on this screen/page. It has height & width, but no depth.

Form is three-dimensional, like a chair. It was height, width, and depth.

Ceramic objects can display both form and shape. For example, a potter can create a 3D vase, and add 2D patterns on its surface.

Principle of Design

Unity when parts of a design combine to create a sense of harmony and oneness.

For example, a potter can achieve a unified design by repeating a colour or a shape.

Movement when a design creates a sense of moving towards something

For example, you can carve flowing lines into the surface.

Lesson 3: Relief

A relief is an image that has been carved or modelled onto a fixed background.

Types of Relief:High relief projects from the surface; almost 3D

Low/Bas relief is elevated, but remains part of the surface

Intaglio the image is incised or carved into the surface

Examples of Relief

A Persian mid-relief located in Iran. May also be called 2 layers of low relief.

"Gates of Paradise" by GhibertiLocated in Florence, Italy.Combination of low and high relief

Examples of Relief

Sunk relief restricted to Ancient Egyptian art. A depiction of Pharaoh Akhenaten with his wife Nefertiti and daughters.

High relief from the Classical GreekElgin Marbles. Located in the British Museum

Lesson 4: Traditional Ceramics

ANCIENT AFRICAN CERAMICSMaking of pottery in Africa began around 6,000B.C.

In ancient times, women were responsible for making pots, as part of food preparation.

All pots were made by hand, using pinching and coil-building and basic tools (like corn husks and rocks).

Ancient African Ceramics

Pots were often polished, or burnished.

Ancient potters also decorated their work with carved geometric designs.

After drying, the pots were put in a pile and covered with wood, bark, or dried cow dung and baked in an open fire.

Ancient African Ceramics

What do you notice about the shape of these vessels?How would you describe the surface designs?

Japanese Tea Ceramics

The tea plant is native to southern China, where tea drinking originated nearly 5,000 years ago.

Tea drinking was spread by Buddhist monks, who used it as part of spiritual ceremonies.

It was adopted by the aristocracy in China and Japan, and soon became a social custom worldwide.

Japanese Tea Ceramics

The Japanese aristocracy developed a very elaborate tea ceremony.

Their goal was to achieve spiritual enlightenment and transformation, demonstrated by harmony, respect, purity, and tranquillity.

This custom led to a special style for tea ceramics.

Japanese Tea Ceramics

Physical variety of textures

Visual looks should match physical traits (if it looks heavy, it should feel heavy)

Outside form should fit comfortably in the hand, and the foot should provide secure balance

Rim should suggest natural movement over stones, hills, or mountains

Drinking point there should be one place for the lip to touch opposite the decorated front of the bowl

Interior form a faint spiral relief should let the tea gently flow into your mouth

Glaze application should vary, but should be harmonious with the form

These are some of the standards that Japanese tea masters used to measure the beauty of a tea bowl:

Examples of Japanese Tea Ceramics
What do you notice about these tea bowls?

Examples of Japanese Tea Ceramics
What do you notice about these tea bowls?

First Nations Ceramics

Ceramics has been around in North and South America for at least 7500 years.

Clay has been used to create cooking vessels, pipes, funerary objects (urns, sculptures), ceremonial items, masks, toys, and sculptures.

Pinch pots and other small objects would be made by hand, without any tools.

Coil-building was also a common technique (Unit 2).

No pottery wheels before European contact.

First Nations Ceramics

Paddle-and-anvil technique: the inside of the clay wall was supported by a mold, and the outside was paddled smooth.

Rope, fabric, baskets, corncobs, and carved wood were rolled over wet clay to add decoration.

Indigenous ceramics were seldom glazed. Instead they were burnished/ polished with a stone. Grease can also be rubbed onto the fired pot to add shine.

Ceramics were usually open-air fired or pit-fired.

Examples of First Nations Ceramics

Iroquoian

Carl Beam (born Carl Migwans) Canadian Ojibwe

Pinch Pot Project

You will create a series of 3 pinch pots.

Since you are creating a series, your 3 pinch pots must have a unifying theme. In other words, they need to look like they go together.

Minimum size for each pinch pot: 4 inches in diameter.

Make them as thin as you can.

Add surface decoration using the techniques mentioned in Lesson 5.

Lesson 5: Decorating Clay

1) Incising carving designs into the surface2) Impressing using an object (like a stamp) to press a design into the clay3) Combing marks the surface with uniform lines; imagine dragging a comb across the clay4) Burnishing rubbing and polishing the clay with a smooth object, like a stone or spoon5) Piercing poking holes in the clay6) Sprigging attaching a decorative piece of clay onto the surface of a piece; ex. - adding small flowers to a teacup

Colouring Clay

1) Oxides - natural minerals found in the earth. Iron produces red; cobalt produces blue; copper produces green; rutile produces tan.

These can be applied before or after firing, but must be fired again to become permanent.

Oxides produce a satin surface.

Colouring Clay

2) Underglazes a combination of oxides, clay, and a flux (ingredient that causes melting).

These can be applied before or after firing, but must be fired to fuse to the clay.

Underglazes create a matte surface.

Colouring Clay

3) Glazes composed of silica ( forms glass when heated), flux (a melting agent), and alumina (stabilizes the glaze so it doesn't run off the object).

Only glaze seals the clay and makes it food-safe. Glaze is best applied after clay has been fired, but must be fired again to fuse to the object.

Glaze produces a glossy surface.

CAUTION

Since oxides, underglazes, and glazes have melting properties, they will fuse to anything they are touching when hot.

When applying oxides, underglazes, or glazes to your work, keep the bottom clean!

Wipe the bottom and 1cm up the walls of your piece with a damp sponge before firing.

Lesson 6: Methods of Applying Colour

1) sponging using a sponge to apply the media

2) brushing using a brush to apply media

3) sgraffito scratching designs into a layer of colour

4) mishima placing colour into incised lines

5) masking using stencils made of paper or masking tape to apply designs onto the clay

Reflection: Unit 1

1) Evaluate your Relief Project: a) Do you think it is a successful artwork? Explain. b) Were you able to create a sense of movement? Explain. c) What would you change if you could?

2) Evaluate your Pinch Pots: a) Do they look like a series? Why or why not? b) Were you able to control the clay successfully? Explain. c) What would you change if you could?