Fused glass is a term used to describe glass that has been
fired (heat-processed) in a kiln at a range of high temperatures from 593? C
(1100'F) to 816? C (1500'F). There 3 main distinctions for temperature
application and the resulting effect on the glass.

Firing in the lower ranges of these temperatures 593?-677'C
(1100? 1250? F) is called slumping. Firing in the middle ranges of these
temperatures 677'C- 732'C (1250?-1350'F) is considered "tack fusing".
Firing the glass at the higher spectrum of this range 732'C -816'C
(1350?-1500'F) is a "full fuse".

All of these techniques can be applied to one glass work in
separate firings to add depth, relief and shape.

 

History

 

Fused glass consists mainly of silica. While the precise
origins of glass fusing techniques are not known with certainty, there is
archeological evidence that the Egyptians were familiar with rudimentary
techniques ca. 2000 BCE. Although this date is generally accepted by all
researchers, some historians argue that the earliest fusing techniques were
first developed by the Romans, who were much more prolific glassworkers. Fusing
was the primary method of making small glass objects for approximately 2,000 years,
until the development of the glass blowpipe. Glassblowing largely supplanted
fusing due to its greater efficiency and utility.

 

While glass working in general enjoyed a revival during the
Renaissance, fusing was largely ignored during this period as well. Fusing
began to regain popularity in the early part of the 20th century, particularly
in the U.S.
during the 1960s. Modern glass fusing is a widespread hobby but the technique
is not widely used for large scale glass production.