Corning Museum of Glass

A tool made from a block of wood hollowed out to form a hemispherical recess. After it has been dipped in water to reduce charring and to create a “cushion” of steam, the block is used to form the gather into a sphere before it is inflated.

A small, heavy object designed to hold down loose papers. The first glass paperweights were made in the early 1840s in Venice and France, and their manufacture spread rapidly to other parts of Europe and the United States. Glass paperweights ceased to be fashionable in the early 20th century, but the craft of making them revived in the 1950s.

Its many meanings include an emblem impressed on wax or some other plastic substance as evidence of ownership or authenticity. Since the 17th century, many bottles have borne stamped glass seals that identify the producer of the contents, the tavern in which they were used, or the individual for whom the contents were bottled.

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.

(German, “gold between glass”) A type of decoration, produced in Bohemia and Austria in the 18th century, in which a design in gold or silver leaf is incorporated between two vessels that fit together precisely. Unlike Hellenistic and Roman gold glass, which is fused, Zwischengoldglas is bonded with cement.

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.

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 fusing or shaping glass (usually in or over a mold) by heating it in a kiln.

An oven used to process a substance by burning, drying, or heating. In contemporary glassworking, kilns are used to fuse enamel and for kiln-forming processes such as slumping.

The technique whereby glass is removed from the surface of an object by grinding it with rotating wheels made of stone, wood, and cork. The first stage of the process employs a stone wheel under a continuous stream of water. Later, wheels of fine-grained stone and wood, fed with various abrasives, are used to grind and polish the surface.

Glass that is colored by (1) impurities in the basic ingredients in the batch or (2) techniques of coloring glass by one of three main processes: (a) using a dissolved metallic oxide to impart a color throughout, (b) forming a dispersion of some substance in a colloidal state, and (c) suspending particles of pigments to form opaque colors.

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.

A type of ornamental glass with an iridescent surface made by spraying the glass with stannous chloride or lead chloride and reheating it under controlled atmospheric conditions. Aurene was developed by Frederick Carder (1863-1963) at Steuben Glass Works in Corning, New York, in 1904.

(French, “glass paste”) A material produced by grinding glass into a fine powder, adding a binder to create a paste, and adding a fluxing medium to facilitate melting. The paste is brushed or tamped into a mold, dried, and fused by firing. After annealing, the object is removed from the mold and finished.

(from French, “new art”) An international late 19th- and early 20th-century decorative style characterized by organic foliate forms, sinuous lines, and non-geometric, “whiplash” curves. Art Nouveau originated in Europe in the late 1880s, and reached the peak of its popularity around 1900. In America, it inspired, among others, Louis Comfort Tiffany (1848-1933). The name is derived from La Maison de l’Art Nouveau, a gallery for interior design that opened in Paris in 1896. The German term for Art Nouveau is Jugendstil.

From French, Exposition Internationale des Arts Décoratifs et Industriels Modernes, an exhibition in Paris in 1925. A style of design that originated in the 1920s and was popular in western Europe and the United States in the 1930s. Art Deco is distinguished by simple, streamlined shapes and frequently by nonrepresentational motifs.

Smoothing the surface of an object when it is cold by holding it against a rotating wheel fed with a fine abrasive such as pumice or cerium oxide. Glass can also be polished with hand-held tools.

A form used for shaping and/ or decorating molten glass. Some molds (e.g., dip molds) impart a pattern to the parison, which is then withdrawn, and blown and tooled to the desired shape and size; other molds (sometimes known as full-size molds) are used to give the object its final form, with or without decoration. Dip molds consist of a single part and are usually shaped like beakers. Full-size molds usually have two or more parts and can be opened to extract the object. Nowadays, most molds are made of metal, but stone, wood, plaster, and earthenware molds were used in the past and are still occasionally employed today.

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

Any cooled glass object that requires further forming or decoration to be finished.

A concavity in the base of a vessel, usually made by depressing the base with a tool. The provision of a kick strengthens the bottom of the vessel and reduces the vessel’s capacity.

These terms are used inconsistently, especially in the context of contemporary glass. When used as a noun, murrina usually refers to a multicolored element embedded in an object, whereas murrine most often refers to slices of a complex cane.

(1) The process of founding or melting the batch; (2) heating pieces of glass in a kiln or furnace until they bond (see Casting and Kiln forming); (3) heating enameled glasses until the enamel bonds with the surface of the 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.

The process of removing glass or imparting a matte finish by bombardment with fine grains of sand that are propelled by compressed air.

A type of borosilicate glass perfected in 1915 by W. C. Taylor and Eugene Sullivan of Corning Glass Works in Corning, New York. Pyrex rods can be used in flameworking.

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

(Italian, “filigree glass”) The generic name for blown glass made with colorless, white, and sometimes colored canes. The filigrana style originated on the island of Murano in the 16th century and spread rapidly to other parts of Europe where façon de Venise glass was produced. Manufacture on Murano continued until the 18th century, and it was revived in the 20th century.

(Italian, “filigree glass”) The generic name for blown glass made with colorless, white, and sometimes colored canes. The filigrana style originated on the island of Murano in the 16th century and spread rapidly to other parts of Europe where façon de Venise glass was produced. Manufacture on Murano continued until the 18th century, and it was revived in the 20th century.

A thin, monochrome rod, or a composite rod consisting of groups of rods of different colors, which are bundled together and fused to form a polychrome design that is visible when seen in cross section.

Glass that contains a high percentage of lead oxide (at least 20 percent of the batch). In modern times, glass of this type was patented in 1674 by George Ravenscroft (1632-1683), who added a larger amount of lead in 1676. Lead glass is relatively soft, and its refractive index gives a brilliance that may be exploited by covering the surface with polished wheel-cut facets. Such glass is often known by the term “lead crystal.”

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.

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.

The process of reheating a blank until it becomes soft and gradually flows under its own weight over or into a former mold and eventually assumes the shape of the mold. Soda-lime glass becomes soft at about 1110°F (600°C). Slumping is also known as sagging.

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

The process of decorating glass by the use of gold leaf, gold paint, or gold dust. The gilding can be applied with size, or amalgamated with mercury. It is then usually attached to the glass by heat. Gold leaf can be picked up on a gather of hot glass.

Any object embedded in the surface of a larger object.

The technique of forming objects from rods and tubes of glass that, when heated in a flame, become soft and can be manipulated into the desired shape. Formerly, the source of the flame was an oil or paraffin lamp used in conjunction with foot-powered bellows; today, gas-fueled torches are used.

The technique of removing the surface of an object with a rotating wheel fed with an abrasive, or by some other means.

The process of (1) heating the batch in order to fuse it into glass by exposing it to the required temperature in a crucible or pot, (2) reheating unfinished glassware while it is being worked, or (3) reheating glassware in a muffle to fuse enamel or gilding. The melting of the batch may require a temperature of about 2400°-2750°F (1300°-1500°C), whereas the muffle kiln may require a temperature of only about 950°- 1300°F (500°-700°C).

The fluid glass produced by melting batch.

(Noun) A mass of molten glass (sometimes called a gob) collected on the end of a blowpipe, pontil, or gathering iron; (verb) to collect molten glass on the end of a tool.

A strand of glass, roughly circular in section, drawn out from a gather.

A container with one handle, used for dispensing liquid.

(from Latin) A jar with two handles.

A small pitcher for serving cream.

A term frequently used to mean all pre-Roman and ancient Roman glass.

A type of Art Glass made by several American factories in the late 19th century. It resembled the peach bloom glaze on 17thto 18th-century Chinese porcelain such as the celebrated Morgan Vase. Most Peachblow glass had a surface that shaded from opaque cream to pink or red, sometimes over opaque white. Similar glass was made in England by Thomas Webb & Sons and Stevens & Williams.

The process of winding a thin trail of glass around an object to create the appearance of parallel lines. In 1876, W. J. Hodgetts of Stourbridge, England, patented a machine that produced very regular and closely spaced threads.

Silicon dioxide, a mineral that is the main ingredient of glass. The most common form of silica used in glassmaking has always been sand.

A hollow stem made by blowing the gather into a mold patterned with two lion’s masks, usually separated by festoons. Lion-mask stems, first used in Venice in the 16th century, subsequently became one of the hallmarks of façon de Venise glass.

The narrow part of a goblet or tazza that separates the bowl and the foot.

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.

A layer of glass that covers a layer of a different color, often as the result of casing or flashing.

The generic term for glass that is manipulated while it is hot.

The removal of glass from the surface of an object by means of hand-held tools or sandblasting.

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.

A monochrome segment of glass cut from a trail.