Definition
When precious metal is heated to temperatures approaching its melting point there is a short span during which the outer layer or skin begins to melt while the interior remains solid. Or, to say the same thing technically, the interior remains in the solidus zone while the surface regions enter the liquid range. The effects are to create an uneven reticulated surface and to allow pieces to join by welding. Every goldsmith discovers fusing, usually by accident and usually as a mistake, when pieces being soldered are overheated.
For years it was accepted in the field that fusing was the result of poor craftsmanship and had no place in the jewelry world. In the 1950's intentionally fused pieces were first shown, pieces that used the rich textures and spontaneous compositions that are part of the process. There was considerable resistance to this "technique" but it has now become adopted as yet another tool in the goldsmith's bag of tricks.
The results of fusing are to some degree dependent upon chance but with some experience the creative effects can be anticipated and controlled. It is easy to distinguish work in which fusing is used for legitimate design purposes from pseudoartistic "works" in which handwork and design inabilities are masked by fusing.