What is Lampworking?
The technology for glass beadmaking is among the oldest human arts, dating back 3,000 years. Glass beads have been dated back to at least Roman times.
A variant of the wound glass beadmaking technique, and a labor intensive one, is what is traditionally called lampworking. In the Venetian industry, where very large quantities of beads were produced in the 19th century for the African trade, the core of a decorated bead was produced from molten glass at furnace temperatures, a large-scale industrial process dominated by men. The delicate multicolored decoration was then added by people, mostly women, working at home using an oil lamp or spirit lamp to re-heat the cores and the fine wisps of colored glass used to decorate them.
Modern lampwork beads are made by using a gas torch to heat a rod of glass and spinning the resulting thread around a metal rod covered in bead release. When the base bead has been formed, other colors of glass can be added to the surface to create many designs. After this initial stage of the beadmaking process, the bead can be further fired in a kiln to make it more durable. Lampworking can be done with many types of glass, but the most common are soda-lime glass, sometimes called "soft glass," and borosilicate glass, often called "hard glass."
Basic "Wound Bead" technique
Preparing the mandrel - The beadmaker starts by dipping a mandrel, or wire (stainless steel welding wire, cut into lengths) into a clay based substance (commonly referred to as "bead release") and letting it dry.
Heating rod and mandrel - The flameworker selects rods of glass to heat in the flame of the torch. When both glass and mandrel are sufficiently warm, the beadmaker starts rotating the mandrel while allowing the glass to wind upon it.
Shaping the bead - Beads are shaped using a combination of heat, gravity and tools such as graphite paddles, mashers, tweezers, and picks. Presses to create shapes and indent patterns into the glass are also used.
Decorating the bead - Beads can be decorated by melting stringers, or fibers of glass on the surface, creating dots or lines. With a sharp pointed tool, feathers, hearts or other designs may be produced. Metal decorations of copper, silver, gold, palladium and platinum are applied as metal leaf, wire, mesh or fuming.
Striking - If silver based colors are used (striking colors), the bead must be heated for a few moments in the torch flame or kiln to allow crystals to reform in the glass. This temperature is slightly above the stress relief point.
Annealing - Once completed, beads should be heated to 940º-1050°F (depending on glass type), until the piece reaches its "stress relief point", held at that temp for a short time, then slowly cooled to avoid thermal shock.
Cold working - The cooled bead can be further decorated. Standard cold working techniques can be employed such as sandblasting, faceting and polishing. Etching the finished piece with acid leaves a matte finish.