Elemental characterization of gold-plated costume jewelry using particle-induced X-ray emission

Abstract

Nine gold-plated costume jewelries bought in the street market of Porto Alegre and from Chinese websites were investigated through Particle-Induced X-ray Emission (PIXE) and Rutherford Backscattering Spectrometry (RBS) in order to verify their elemental composition and distribution. The analyzed costume jewelries were made of Cu-based alloys with Ni, Zn, Sn and Al. Elements such as Ag, Al, Bi, Cd, Co and Fe were found in minor amounts in some particular samples. Through RBS, it was possible to distinguish the bulk from the gold-plated layer. Toxic elements as Ni and Cd were found in at least one sample. The high concentration of Ni comes from the bulk Cu-alloy below the Au layer. In this case, the Au acts as a protective layer separating the Ni from the user’s skin.