Basics of Ceramics Ceramics Defined Pottery or hollow

Basics of Ceramics

Ceramics Defined • Pottery or hollow clay sculpture fired at high temperatures in a kiln to make them harder and stronger.

Types of Clay: Stoneware • High Fire (Cone 5 -10) • From the earth • A buff, gray or brown • Mixed with other clays and ceramic materials to make a heavy, opaque, highly plastic clay body

Earthenware • fired at relatively low temperature, may be glazed or unglazed, and is usually but not always buff, red, or brown in color. • pottery or other objects made from fired clay which is porous and permeable

Greenware • unfired pottery

Stages of Clay • Leather-Hard: a state in which clay has lost moisture to evaporation, but has not yet completely hardened; clay damp enough to be joined to other pieces with scoring and slip.

Stages of Clay • Bisque: Clay that has been fired once but not glazed • Bone Dry: greenware which is thoroughly room dried.

Tools • Loop Tool – consisting of a loop of metal attached to a handle, and used in carving leather-hard clay. • Pin Tool – used to scratch the surface of clay for scoring or other markings.

Techniques • Score – to make scratches or creases in pieces of clay to be joined together. • Slip – an opaque, creamy liquid made by mixing finely ground clay with water.

Technology • Kiln – special oven or furnace that can reach very high temperatures and is used to bake, or fire clay. • Pyrometric cone – made of ceramic clay placed inside kiln before firing designed to melt at certain temperature.

Finalize • Glaze – thin coating of minerals which produces a glassy transparent or colored coating on bisque ware. • Underglaze - create designs and patterns that will come up through the glaze covering them, which can give the surface more visual depth and character.