Ceramics Glazing Vocabulary & Concepts
Kiln – A high temperature oven for baking potters clay. The baking process in a kiln is called firing.
Bisque Fire– The first firing of potters clay. Bisque Ware – Ceramics fired at a temperature sufficient to harden but not mature the body.
Maturity – When a clay body develops maximum non-porosity or hardness. It may also occur when glaze ingredients enter into complete fusion and bonds firmly with the pottery clay body.
Absorbency – The ability to soak up moisture.
Wax Resist – A wax emulsion used to prevent glaze from adhering to bisque ware. It can be used for decorating ceramics, and on the foot and foot rim to prevent glaze from running onto the kiln shelf.
Glaze – A suspension of fine minerals (including silicon) for coating on bisque ware. The glaze melts into a glassy surface on the ceramics when fire. Wet glaze should have the consistency of heavy cream and can be applied using many different techniques, including brushing, dipping, and pouring. Always stir glazes (shake well) because the sediments settle to the bottom of the containers. Cover glazes tightly to prevent lose of moisture and spills. After the glaze dries the ceramic objects can be fired to a temperature that melts the glaze. Clean brushes and stir sticks before changing glazes to keep glazes pure.
Glazing 2
Dampen bisque ware surface - Quickly rinse bisque ware under a tap or wipe it with a clean sponge to remove dirt, and to prevent pin hole air bubbles on the glazed surface. Do not dampen red tiles because they have a mature body and therefore absorbs little moisture.
Clean foot & foot rim – The glaze must be cleaned completely off the bottom foot of the pottery and ¼ inch up the side. Really thick areas of glaze should never be near the bottom rim of your pottery because glaze can run and drip causing damage to the kiln shelves.
Combing – A method of decoration developed by dragging a comb or fork over two contrasting layers of wet glaze.
Spatter – A glazing technique where you use a toothbrush to flick glaze creating small dots, which can causing a sandy appearance.
Blending – A low fire glazing technique where two colors are overlapped to blend or combine them in the center. High fire glazes may react differently and not work.
Dimensional glaze – A thick glaze that you squeeze out of a small bottle to create line that have some height.
Ceramic decorating pencils – A stain or oxide in pencil form that allows for fine line drawings to be made on pottery, which is normally difficult to achieve.