Corning Museum of Glass

A movement that began in the United States in the 1960s and has spread all over the world. It is characterized by the proliferation of glass artists who are not affiliated with factories, but work with hot glass in their own studios. The emergence of independent glass artists was made possible by Harvey Littleton and Dominick Labino’s development in 1962 of a small furnace and easy-to-melt glass.

A term popularized in the 1960s for unique or limited-edition objects designed and made in a studio rather than a factory, often, but not necessarily, by the same person.

A vitreous substance made of finely powdered glass colored with metallic oxide and suspended in an oily medium for ease of application with a brush. The medium burns away during firing in a low-temperature muffle kiln (about 965°-1300°F or 500°-700°C). Sometimes, several firings are required to fuse the different colors of an elaborately enameled object.

The technique of forming an object by inflating a gather or gob of molten glass on the end of a blowpipe. Traditionally and in modern furnace working, the gaffer blows through the tube, slightly inflating the gob, which is then manipulated into the required form by swinging it, rolling it on a marver, or shaping it with tools or in a mold. It is then inflated to the desired size. In flameworking, one end of the glass tube is heated and closed immediately, after which the worker blows into the other end and manipulates the hot glass.

Objects made from preformed elements placed in a mold and heated until they fuse. The term “mosaic glass” is preferable to “millefiori,” except in the case of Venetian or façon de Venise glass.

Glass of one color covered, usually by casing, with one or more layers of contrasting color(s). The outer layers are acid-etched, carved, cut, or engraved to produce a design that stands out from the background. The first cameo glasses were made by the ancient Romans. The genre was revived in England and, to a lesser extent, in America in the late 19th century.

The rainbowlike effect that changes according to the angle from which it is viewed or the angle of incidence of the source of light. On ancient glass, iridescence is caused by interference effects of light reflected from several layers of weathering products. On certain 19th- and 20th-century glasses, iridescence is a deliberate effect achieved by the introduction of metallic substances into the batch or by spraying the surface with stannous chloride or lead chloride and reheating it in a reducing atmosphere.

The term applied to several types of Hellenistic and ancient Roman glass objects decorated with designs cut and/or engraved in gold leaf, which is sandwiched between two fused layers of glass. Hellenistic gold glass was made by sandwiching the decoration between two closely fitting cast, ground, and polished vessels, which were then fused. Many Roman gold glasses apparently were made by applying the gold leaf to the surface of an object, reheating it, and inflating a parison against the decorated surface.

An ancient Roman vessel decorated by undercutting so that the surface decoration stands free of the body of the glass, supported by struts. The vessel appears, therefore, to be enclosed in an openwork cage. Cage cups are sometimes known as diatreta or vasa diatreta.

A surface decorated with many small, adjoining pieces of varicolored materials, such as stone or glass.

Quartz (chemically pure silicon dioxide), which is usually colorless. From earliest times, glassmakers sought to imitate it.

Deep red glass colored by the addition of gold chloride to the batch. The method of making gold ruby glass was perfected by Johann Kunckel (1637-1703) in Potsdam shortly before 1679.

An enclosed structure for the production and application of heat. In glassmaking, furnaces are used for melting the batch, maintaining pots of glass in a molten state, and reheating partly formed objects at the glory hole.

A popular term for colorless lead glass, which has a high refractive index and consequently is particularly brilliant. In the United Kingdom, glass described as crystal must contain a defined percentage of lead oxide. Today, the word is often used to describe any fine glass tableware.

The generic name for decorative windows made of pieces of colored glass fitted into cames and set in iron frames. Strictly speaking, the term is inaccurate because, in addition to glass colored by staining, glaziers used, and continue to use, glass colored throughout by metallic oxide, glass colored by flashing, and glass decorated with enamel.

The process of cutting into the surface of an annealed glass object either by holding it against a rotating copper wheel fed with an abrasive or by scratching it, usually with a diamond.

(1) A rounded, hollow vessel; (2) the uppermost part of a goblet, tazza, or wineglass.

The generic name for a wide variety of techniques used to form glass in a mold.