Study of the 19th century porcelain cards with direct Raman analysis

Porcelain cards are a special type of cards, which are typical of the 19th century. They are produced by a lithographic procedure, and painted by hand. In this work, direct non‐destructive Raman spectroscopy is used to analyse the pigments that were used during the production of 43 porcelain cards, originating from different locations. Apart from the metals, which do not yield a Raman spectrum, the pigments could be identified, including vermilion, red lead, lead white, Prussian blue, ultramarine, carbon black and chrome yellow. In some cases pigment mixtures were applied, to produce purple, brown and green colours. Although a wide range of porcelain cards were analysed, the pigment use on these cards is remarkably constant, including synthetic pigments that were only recently (at the time) produced. Therefore, no obvious differences, which could be related to the provenance, could be identified.