-What are Lampwork Beads?

Lampworking is glassworking using a torch to melt and shape the glass. It is also known as flameworking or torchworking, as the modern practice no longer uses oil-fueled lamps. Although the art form has been practiced since ancient times, it became widely practiced in Murano, Italy in the 14th century. In the mid 19th century lampwork technique was extended to the production of paperweights, primarily in France, where it became a popular art form, still collected today.

 Early lampworking was done in the flame of an oil lamp, with the artist blowing air into the flame through a pipe. Most artists today use torches that burn either propane or natural gas for the fuel gas, with either air or pure oxygen (which can be produced by an oxygen concentrator) as the oxidizer. 

 General methods After designing a piece, a lampworker must carefully plan how to construct it. Once ready to begin, the lampworker slowly introduces glass rod or tubing into the flame to prevent cracking from thermal shock. The glass is heated until molten, wound around a specially-coated steel mandrel, forming the base bead. It can then be embellished or decorated using a variety of techniques and materials. All parts of the workpiece must be kept at similar temperatures lest they can or shatter. Once finished the piece must be annealed in an oven to prevent cracking or shattering.

Glass selection

  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. 

 Annealing, in glass terms, is heating a piece until its temperature reaches a stress-relief point, that is, a temperature at which the glass is still too hard to deform, but is soft enough for internal stresses to ease.  The piece is then slowly cooled at a predetermined rate until its temperature is below a critical point, at which it can't generate internal stresses, and then can safely be dropped to room temperature. This relieves the internal stresses, resulting in a piece which should last for many years. Glass which has not been annealed may crack or shatter due to a seemingly minor temperature change or other shock.

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