PAINTED GLASS — Glass on which special paints (containing frit) have been applied in illustration or decorative pattern and then heated in a kiln to a temperature high enough to fuse the pigments permanently to the glass surface. The modern version of the original medieval "stained glass."
PARISON — A gather on the end of a blowpipe that is already inflated.
PATE DE VERRE — A French term meaning "glass paste," pate de verre is the technique of creating a solid form from a glass powder or frit. The "glass paste" is brushed or tamped into a mold and fused together in a kiln to form a solid object. A frit casting technique
PATTERN BAR — A bundle of glass that has been fused together to form a solid shape.
PATTERN SLICES — Thin slices cut off a pattern bar.
PEEP HOLE — Small hole(s) in a kiln designed for viewing the contents of the kiln chamber. Also used to ventilate the firing chamber.
PINCERS — A glassworker's tool used for decorating objects by pinching the glass while it's hot.
PINCHING — A method of forming clay, which is well described by its name.
PINCH POT — Pinch pots are the classic pottery projects for beginners. By pinching, or working clay with one's thumbs, fingers, and palms, one creates a pinch pot - a simple, hollowed-out piece of clay.
PLASTER — 2CaSO4 2H2O. An invaluable mold-making tool for the potter, also used extensively in industry. It can be poured or carved into virtually any shape. When it is dry it can be used to press clay into or to slipcast with.
PLASTICITY — The properties of a material that allow it to be shaped and to retain its shape. The plastic properties of clay are principally determined by the size of the platelets. The smaller the platelets the more plastic the clay is. Aging or souring is also relevant to a clays plasticity; with time bacterial action creates a colloidal gel, which aids the lubrication of the platelets. It refers to the ease with which a particular type of clay or clay body can be formed into different shapes without breaking or cracking.
PLIABLE ZONE — Also referred to as the workable zone. Glass will begin to slump or move from about 1250 degrees Fahrenheit to 1350 degrees Fahrenheit. This is the zone where glass slumping occurs.
POLISHING — The process of smoothing the surface of an object by holding it against a rotating wheel fed with a fine abrasive such as pumice or cerium oxide. Glass can be polished with hand held tools as well.
PONTIL MARK — refers to the place on the base of a glass object where it is attached to the punty rod or pontil while the blower is shaping and finishing the piece, and then snapped off and polished smooth.
PORCELAIN — A white, highly vitrified, high firing clay body that is translucent where thin. The translucency is a result of silica glass fused into the fired clay. To achieve this a high amount of flux is added to a kaolin based clay body.
POT FURNACE — A melting chamber in which one or more ceramic pots are placed. Batch is fed into the individual pots through ports in the chamber walls, and when melted, glass is ladled from the pots via the same ports. Each pot is fairly small. The pot furnace allows the melting of a number of different glass colors (as many as there are pots) at the same time, within a single melting chamber.
POTTERS WHEEL — A potter's wheel, aka potter's lathe or pottery wheel, is a machine with a rotating wheel on which a potter shapes or "throws" clay. Pottery wheels can be driven by electricity or by hand power or foot power (the latter are known as kickwheels).
POWDERS — Glass that has been ground into a fine powder. It can be used to decorate glass before fusing, mixed with liquid stringer and used as paint, or mixed with water and used in the Freeze and Fuse method.
PREFIRE ADHESIVE — Glue that can be used to hold glass in place before firing.
PRESSED GLASS — Glassware formed by placing a blob of molten glass in a metal mold and pressing it with a metal plunger or “follower” to form the inside shape. The resultant piece, termed “mold-pressed” has an interior form independent of the exterior, in contrast to mold-blown glass, whose interior corresponds to the outer form.
PRUNT — A small blob of glass fused to a piece of glass, often impressed with a pattern or stamp.
PUNTY, OR PUNTIL ROD — refers to the metal rod a glassmaker attaches to hot glass so that it can be handled while hot as the piece is shaped and finished. When the punty is removed it often leaves a scar on the base of the object called the pontil mark or punty mark, which is usually polished out of final art works.
PUG MILL — Pug is the act of mixing clay, and pug mills are machines that perform this task. Pugmills can be used to create clay recipes, recycle clay, mix it with water, or eliminate air bubbles from clay.
PYROMETER — A meter that indicates temperatures inside the kiln. In order to work, a pyrometer must have a thermocouple (temperature sensor) connected to it.