Stained Glass
The term "stained glass" today generally refers to glass that has been colored by added metallic salts during its manufacture. For example, using the metal copper would produce green or blue glass. more...
The molten glass is then annealed slowly in a furnace to produce sheets of colored glass. Early stained glass artists were limited to a very few primary colors, but today almost any color can be produced.
If fine details such as shadows or outlines are required, the artist paints them on the cold glass with special paint made from metal oxides. The piece is then fired in a kiln. This process is, in itself, an art. The oxides permanently fuse with the glass to produce the painting. This is where we have derived the term "stained glass".
These colored glasses are available in many different textures—smooth, wavy, rippled, hammered, pebbled, or very rough. These different textures cause the glass to have light and color transmission characteristics that, even for the same color, can provide surprising results. Stained glass is sold by weight and by square foot in sheets, usually about 3' x 4'.
Stained glass windows involve the art of cutting colored glass into different shapes, then assembling the pieces using channeled lead-came strips, or copper-foil. Once assembled, the pieces are then soldered together and installed in a frame to create a window. For technical details, see Lead came and copper foil glasswork.
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