An electrochemical methodology for discriminating monetary emissions, a recurrent problem in much archaeological studies, is introduced. The method is based on the record of voltammetric signatures of cuprite and tenorite corrosion products in the patina using a minimally invasive nanosampling following the voltammetry of immobilized particles methodology. A model for the depth variation of voltammetric electrochemical parameters characterizing the composition of the corrosion patinas is presented. This model permits to rationalize electrochemical data and discriminate different monetary emissions. The application of this technique, corroborated by electrochemical impedance spectroscopy (EIS) and focusing ion beam-field emission scanning electron microscopy (FIB-FESEM-EDX), to a series of 10 cash copper coins produced around the Kuang Hsu and Hsüan T'ung last Chinese emperors permits to discern different provincial mints and reveals that the monetary unification developed in this period was not uniform.

The use of Raman spectroscopy for discriminating monetary emissions, a recurrent problem in much archaeological studies, is described. The method involves the record of Raman signatures of tenorite and crystalline and defective cuprite in the patina based on the idea that subtle, mint‐characteristic variations in the composition and metallography of the base metal during the manufacturing process are reflected in the variation in depth of the composition and crystallinity of the corrosion patina. The technique was applied to a series of 10‐cash copper coins produced around the transition between the Kuang Hsü and Hsüan T'ung last Chinese emperors and the first Republic whose averaged composition was 95 ± 1% wt Cu plus 5 ± 1% wt Zn often accompanied by traces of Sn and Pb. Raman data, corroborated by focusing ion beam‐field emission scanning electron microscopy and voltammetry of immobilized particles measurements, suggested the possibility of discerning between different provincial and regular unified currency productions.

The oblique collisions between two axisymmetric disks moving on a flat horizontal surface are described in terms of impact modeling based on the assumption that normal and tangential restitution mechanisms operate independently of friction. Describing these mechanisms in terms of the usual Coulomb formulation, the model allows for an interpretation of some "anomalous" experimental data reported in the literature. These experimental data, corresponding to the variation of the coefficients of friction and tangential restitution with the impact angle, remained unexplained in classic formulations, are understood within the framework of the independent friction-restitution closure. Experimental data for metallic coins are in agreement with that formulation, including rolling friction effects.