Stained glass
Stained glass is coloured glass as a material or works created from it. Throughout its thousand-year history, the term has been applied almost exclusively to the windows of churches and other significant religious buildings. Although traditionally made in flat panels and used as windows, the creations of modern stained glass artists also include three-dimensional structures and sculpture. Modern vernacular usage has often extended the term "stained glass" to include domestic lead light and objets d'art created from foil glasswork exemplified in the famous lamps of Louis Comfort Tiffany.
For other uses, see Stained glass (disambiguation).
As a material stained glass is glass that has been coloured by adding metallic salts during its manufacture, and usually then further decorating it in various ways. The coloured glass is crafted into stained glass windows in which small pieces of glass are arranged to form patterns or pictures, held together (traditionally) by strips of lead, called cames or calms, and supported by a rigid frame. Painted details and yellow stain are often used to enhance the design. The term stained glass is also applied to windows in enamelled glass in which the colours have been painted onto the glass and then fused to the glass in a kiln; very often this technique is only applied to parts of a window.
Stained glass, as an art and a craft, requires the artistic skill to conceive an appropriate and workable design, and the engineering skills to assemble the piece. A window must fit snugly into the space for which it is made, must resist wind and rain, and also, especially in the larger windows, must support its own weight. Many large windows have withstood the test of time and remained substantially intact since the Late Middle Ages. In Western Europe, together with illuminated manuscripts, they constitute the major form of medieval pictorial art to have survived. In this context, the purpose of a stained glass window is not to allow those within a building to see the world outside or even primarily to admit light but rather to control it. For this reason stained glass windows have been described as "illuminated wall decorations".
The design of a window may be abstract or figurative; may incorporate narratives drawn from the Bible, history, or literature; may represent saints or patrons, or use symbolic motifs, in particular armorial. Windows within a building may be thematic, for example: within a church – episodes from the life of Christ; within a parliament building – shields of the constituencies; within a college hall – figures representing the arts and sciences; or within a home – flora, fauna, or landscape.
Techniques[edit]
"Pot metal" and flashed glass[edit]
The primary method of including colour in stained glass is to use glass, originally colourless, that has been given colouring by mixing with metal oxides in its melted state (in a crucible or "pot"), producing glass sheets that are coloured all the way through; these are known as "pot metal" glass.[2] A second method, sometimes used in some areas of windows, is flashed glass, a thin coating of coloured glass fused to colourless glass (or coloured glass, to produce a different colour). In medieval glass flashing was especially used for reds, as glass made with gold compounds was very expensive and tended to be too deep in colour to use at full thickness.[3]
Thomas Becket window from Canterbury showing the pot metal and painted glass, lead H-sectioned cames, modern steel rods and copper wire attachments.
