Vocabulary Vocabulary Basics Clay a wet mixture of

Vocabulary

Vocabulary - Basics • Clay – a wet mixture of silica and alumina and other fillers • Slip – a thick watery mixture of clay used to decorate or join • Glaze – a glassy finish for ceramics made from silica

Vocabulary – Stages of Clay • Greenware – dry clay that has not been fired • Leatherhard – clay that is dry enough to stand up but can be cut, carved and bent • Bonedry – chalky, dry clay that is ready for the kiln • Bisqueware – clay that has been heated in the kiln, all water has been removed • Glazeware – clay that has a glass-like coating, usuall it has been fired twice

Vocabulary – Properties of Clay • Plasticity – how easy the clay is to work, holds form well • Workability – how easy the clay is to manipulate • Porosity – how much water the fired clay sucks up in a set amount of time • Vitrification – how hard the clay gets when fired

Vocabulary – Mixing Clay Silica – a element present in clay Alumina – an element present in clay Mixing – putting different types of clay together Contamination – other non-clay materials that will burn out in the kiln • Purity – how clean the clay body is • Grain – how gritty the clay is, effects how smooth you can make it • •

Vocabulary – Firing Clay • Cone Temperature – how hot the kiln gets • Kiln – an enclosed oven that heats to a high temperature for ceramics • Fire – heating the clay to a certain temperature in a kiln • Bisque – the first firing, normally a lower temperature • Glaze Firing – usually the second firing, higher temperature and more precautions taken