Glossary T

TACK FUSING — Fusing glass until it just sticks together. Each piece still retains its individual character.

TAGLIA — A square-ended knife used to shape or sculpt molten glass on the blowpipe.

TEARDROP — Refers to an inclusion caused by an air bubble, purposely created in a glass item for decorative effect to highlight a feature such as the stem of a goblet or the stopper of a decanter.

TERRAZZO — A combination of marble, granite, onyx, or glass chips in a binder of portland cement or other resinous material. After curing, the surface is ground to expose the decorative chips.

TERRA SIGLLIATTA — A slip comprised of the smallest particles of clay, which consequently resembles a burnished surface. The technique was used to impressive effect in the Greco-Roman period.

TESTED COMPATIBLE — Descriptive of glasses which have been tested and marked prior to sale to verify compatibility with each other when combined in a hot glass process like blowing, fusing, or casting.

TEXTURE FIRE — Fusing glass to the point where it is bonded and the texture remains on the individual pieces.

TEXTURE PAD — Earthenware molds that add texture to glass.

TEXTURED GLASS — A sheet of hand cast or machine made glass that has had one side embossed with a texture. Rolled textures: In rolled glasses (see definitions below), one of the forming rolls is embossed with a texture that is imprinted on the glass as the sheet is formed. This produces glass smooth on one side and textured on the other. Common examples are "hammered," "granite," and "muffle." Natural textures: any textural effect created without mechanical influence or embossed rolls. Includes Baroque and Waterglass®. Cold glass textures: this category includes glue chipping, etching, sand blasting, and any other surface treatment performed on the cold glass sheet at room temperature.

THERMAL SHOCK — Breakage that occurs in glass because of rapid heating or cooling.

THERMOCOUPLE — The temperature sensing probe of a pyrometer. It's inserted into the kiln chamber to measure temperature.

THREADING — The process of winding a thin trail of glass around an object to create the appearance of parallel lines.

THROWING — To make pottery by hand on the potters wheel. A delicate balance, which defies gravity and centrifugal force as clay is coaxed up by hand from a spinning turntable.

TOOL — General term that describes any tool used by glassworkers during the glassmaking process. Glassworker's tools include the blowpipe, pontil, gathering iron, jacks, shears, clapper, pallet, block, pincers, battledore, lipper, and crimper.

TOP FIRING KILN — The elements are placed in the lid of the kiln.

TRAIL — A strand of glass, roughly circular in section and drawn out from a gather, used to decorate the surface of a glass object.

TRANSITIONAL ZONE — Glass begins to change from about 900 degrees Fahrenheit to 1250 degrees Fahrenheit. The strain point is at the lower end of this temperature, while the upper end is where the softening point and the annealing point are near the same temperature.

TRIMMING OR TURNING — Certain forms made on the potter’s wheel will not support themselves unless excess clay is left at the base, alternatively, extra definition on the foot of a pot may be needed. The solution to both these problems is turning, which is done at the leather hard stage. The pot is inverted onto a potter’s wheel and a metal cutting tool is applied to the bottom of the pot until the desired finish is achieved.

TURN — Refers to a shift worked by a shop and measuring output by how many pieces were produced rather than the number of hours worked.

TWISTIES —  Cane formed out of different colored glass twisted together.