Cathedral glass

Cathedral glass is the name given commercially to monochromatic sheet glass, which is thin by comparison with "slab glass", may be coloured and is textured on one side.

The name draws from the fact that windows of "stained glass" were a feature of medieval European cathedrals from the 10th century onwards.

The term "cathedral glass" is sometimes applied erroneously to the windows of cathedrals as an alternative to the term "stained glass". "Stained glass" is the material and the art form of making coloured windows of elaborate or pictorial design.

Traditional methods of making stained glass

Most early "stained glass" was made by mouth-blowing long cylinders of molten glass, which were partly cooled, had the ends removed, were cut open, reheated and flattened.

A second technique that was employed was to pour the molten glass onto a metal table top. The upper surface was smooth and glossy but the lower surface produced an irregular knobbly patterning caused by the way in which the glass reacted with the cold metal surface. The knobbles have the appearance of having been hammered flat.

In the modern glass manufacturing and trading process, it is glass that has the characteristics of the latter that is referred to as "cathedral glass".

Modern methods of making cathedral glass

Modern "cathedral glass" may superficially resemble table-poured glass but close examination may show a regularity in the texture and a dullness of surface that indicate it has been moulded. It is usually machine made, much of it being manufactured in China.

In England and Germany some "cathedral glass" is still manufactured by more traditional table-poured means by companies which specialise in the production of glass for restoration purposes and which also make cylinder glass.

"Cathedral glass" comes in a very wide variety of colours and surface textures including hammered, rippled, seedy, and marine textures.

Uses of cathedral glass

During the late 19th century and the first three decades of the 20th century, much "cathedral glass" was used for decorative lead lighting in domestic and commercial buildings, most often in conjunction with drawn sheet glass and sometimes with decorative sections of bevelled glass as well. "Cathedral glass" was also used extensively throughout the 20th century in non-pictorial windows in churches where it was an inexpensive alternative to stained glass, yet created a pleasant ambiance because of the filtered light and colour.

The major modern use for "cathedral glass" is in the glazing of bathroom and toilet windows and panels in front doors in order to let in light but reduce visibility.

Much of the more brightly-coloured "cathedral glass" is sold in small sheets measuring 12x12 inches to hobbyists and commercial manufacturers of small "lead light" and "stained glass" objects, such as table lamps.

It is also used for the creation of modern stained glass windows in which the texture of the glass is treated, with the colour, as a significant design element.

See also

* Architectural glass
* Beveled glass
* Drapery glass
* Fracture glass
* Fracture-streamer glass
* Lead came and copper foil glasswork
* Leadlight
* Ring mottle glass
* Rippled glass
* Streamer glass
* Stained glass
* Stained glass - British glass, 1811-1918

References

* Sarah Brown, "Stained Glass, an Illustrated History" 1995, Bracken Books, ISBN 1-85891-157-5

* Ben Sinclair, "Plain Glazing", 2001, the Building Conservation Directory, [http://www.buildingconservation.com]