Although lampworking has been around thousands of years, it isn't until just recently that lampworked glass has been regarded as anything other than a novelty medium. This is strange because when looked at carefully, lampworking is an extremely versatile craft with capabilities far exceeding what is possible with a punti and a blowpipe.
Instead of a furnace, a lampworker uses a torch or bench burner to heat his glass. He works with a much smaller volume of heat than a glassblower and usually a smaller quantity of glass. The resulting proliferation of low quality diminutive work has led to the lack of respect that lampworkers have traditionally suffered. However, all that is quickly changing. Here's why.
The most basic difference between "offhand glassblowing" and lampworking is that lampworkers can selectively heat different parts of a piece whereas a glass blower must repeatedly reheat his entire piece. This means that the lampworker is capable of doing far more intricate and detailed operations than a glass blower. The down side of this is the additional strain put on the glass due to uneven heating, which when allowed to go too far, will cost the lampworker his piece. Consequently, every lampworker develops a kind of "seat-of-the-pants" feeling for the limitations of his medium. This has also led to the development of materials that better withstand the thermal abuse of being heated at the lamp. One such material is borosilicate glass.
Borosilicate glass is composed largely of uncombined silica mixed with boron and a little aluminum. It has no lead and very little sodium in it. This formula lowers the expansion coefficient to about a third of that of leaded glass making it far more resistant to thermal shock. Its melting temperature is too high for practical use by glassblowers, but for a lampworker using a Oxygen-gas flame, it is ideal. Working with borosilicate glass, lampworkers are able to do incredibly complex pieces, and much larger than was ever possible with lead or soda lime glass. A skilled lampworker can work a single piece of borosilicate glass all day with little risk of shattering as long as he keeps it hot. Assemblages, pieces constructed of two or three or more pre-made parts and then assembled cold before annealing are also possible. Another tremendous advantage made possible by the use of borosilicate glass is the facilitation of repairs made to damaged pieces. What would be impossible to fix in soda lime or lead glass requires little more than a quick reheating and a few seconds of labor with borosilicate glass.
One of the biggest drawbacks to borosilicate glass however, was that it was not available in color. In fact, the best brands of borosilicate glass, like Pyrex, are as clear as the finest lead crystal. If a lampworker wanted to have color in his work, he was pretty much on his own. It was a lampworker named John Burton in the 1960's who first came up with a way to color borosilicate glass by using metallic oxides. His knowledge has since evolved into a considerable industry and a rather wide range of borosilicate colored glass suitable for lampworking is available today. There is still not the vast palette available in soda lime and lead glass, but there is enough so that an enterprising and skilled lampworker can do almost anything he desires... except match the drapes.
Although I work with all types of glass including lead and soda lime, most of my work is done with borosilicate glass. I prefer the freedom of expression it allows me and find that the pieces are more durable and far easier to maintain. I believe we are currently at the beginning of a lampworking revolution that will result in development of even more superior materials and techniques. But nothing can ever replace the artist, and it is up to every individual lampworker to realize their full potential as an artist and try to work toward that end. We don't ever want to go back to being thought of as "novelty" makers only.
Robert A. Mickelsen 1992