Laser-induced breakdown spectrometry in jewellery industry. Part II: quantitative characterisation of goldfilled interface.

A new application of laser-induced breakdown spectrometry (LIBS) and multivariate data analysis, namely partial least-squares regression (PLS) in the jewellery industry is reported. The method was designed for the quantitative characterisation of the interface of goldfilled, a material widely used in costume jewellery fabrication, by monitoring the emission lines of the elements present in the sample, while subjecting the piece to a number of laser pulses. The method also provides quantitative information about the composition of a given layer of the material of a special interest at the interface in order to know the existence of diffusion phenomena.