The collective term for the many techniques (such as copper-wheel engraving and cutting) used to alter or decorate glass when it is cold.

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.

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

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.

Any crystalline inclusion present in glass. Stones consist of unmelted particles of batch, fragments of refractory material from the pot, or devitrification crystals. Stones of the first two varieties are generally irregular but rounded; those of the third variety are angular and well formed.

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

(1) Several types of glass with newly developed surface textures, shaded colors, or casing, made in the United States from about 1870 and in Europe between about 1880 and 1900; (2) more generally, especially when written “art glass,” any ornamental glassware made since the mid-19th century.

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 most common form of silica used in making glass. It is collected from the seashore or, preferably, from deposits that have fewer impurities. For most present-day glassmaking, sand must have a low iron content. Before being used in a batch, it is thoroughly washed, heated to remove carbonaceous matter, and screened to obtain uniformly small grains.