Corning Museum of Glass

In glassmaking, a soluble salt consisting mainly of potassium carbonate or sodium carbonate. It is one of the essential ingredients of glass, generally accounting for about 15-20 percent of the batch. The alkali is a flux, which reduces the melting point of the major constituent of glass, silica.

The mixture of raw materials (often silica, soda or potash, and lime) that is melted in a pot or tank to make glass. Cullet, as well as minor ingredients such as colorants, can be added to the batch to help the melting process.

The application of a layer of glass over a layer of contrasting color. The gaffer either gathers one layer over another gather, or inflates a gob of hot glass inside a preformed blank of another color. The two components adhere and are inflated together (perhaps with frequent reheating) until they have the desired form. Sometimes, the upper layer is carved, cut, or acid-etched to produce cameo glass.

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.

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

(from Old French nef, “ship”) A table ornament in the form of a ship, with the hull formed by blowing and the rigging consisting of trails. Sometimes, there is a spout in the hull.

Neon is an inert gas that, like some other gases, has the properties of high electrical conductivity and strong light-emissive power. Such gases can be introduced into evacuated glass tubes. Under these conditions, an electrical discharge causes the gas to emit light. Different gases emit different colors; for example, neon emits red, and xenon emits blue. Regardless of the gases employed, lighting of this type is known as neon lighting.

Neon is an inert gas that, like some other gases, has the properties of high electrical conductivity and strong light-emissive power. Such gases can be introduced into evacuated glass tubes. Under these conditions, an electrical discharge causes the gas to emit light. Different gases emit different colors; for example, neon emits red, and xenon emits blue. Regardless of the gases employed, lighting of this type is known as neon lighting.

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

(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.

Usually, the post at the head and the foot of a flight of stairs, supporting the handrail. In the 19th century, glass finials were sometimes used to adorn newel posts.

An ornamental knob.

Usually, the post at the head and the foot of a flight of stairs, supporting the handrail. In the 19th century, glass finials were sometimes used to adorn newel posts.

The technique of manipulating adjacent vertical ribs with pincers to form a diamond pattern. “Nipt-diamond-waies” was the term used by the English glassmaker George Ravenscroft (1632-1683) in a 1677 advertisement for his new lead glass.

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 glassworker’s tool used for decorating objects by pinching the glass while it is hot.

A blob of glass applied to a glass object primarily as decoration, but also to afford a firm grip in the absence of a handle.