Clay

Clay is a very fine mineral mixture composed of a variety of hydroxide minerals. These hydroxides can be fired to produce ceramic materials.

Uses

Primary

• Production of ceramics

Secondary

• As a solid substrate for reacting solid materials (used when other more common solvents like water are impractical)

Natural occurrence

• Clay occurs naturally

Components

Primary

• The silicon component is most often kaolinite
• The aluminum component is most often bauxite

Trace

• Iron as goethite
• Magnesium as brucite or as the -carbonate.
• Calcium, Sodium, and Potassium can be present as -carbonates.

Types

Pottery

Pottery clay is primarily kaolinite

Brick

Brick clay contains kaolinite, mullite and silicon dioxide

Firebrick

Fire clay contains kaolinite and bauxite with some mullite and aluminum oxide