CANDLING
ca: PREESCALFAMENT
es: PRECALENTAMIENTO
Candling is to fire clay very slowly in the first stage of firing until it reaches the temperature of boiling water. This is done to prevent cracking, breaking and explosions which are often caused when the clay is thick and the outside is dry but the inside still damp. If the object is not candled, the heat and gases cannot escape and their pressure against the outside wall of dry clay forces it, so it breaks.
