By March 2013 all European Community countries will be required to align to a new nickel release test method launched in 2011. The new rules change the artificial sweat solution used for testing and eliminate the 0.1 correction factor that was in the old standard to compensate for uncertainty in measurement results. Nickel release values provided by alloy manufacturers are for as-cast and annealed wrought conditions of each alloy. The two values can differ significantly, so it is interesting to evaluate the nickel released from an alloy in all the conditions derived from the various work cycles of jewelry production. In this paper, we map the nickel released from various 18K white-gold alloys after casting, soldering, laser welding, stamping, punching, rolling and polishing to see how different alloy conditions resulting from various working processes influence the release.

Author(s): Silvia Bezzone