Pigments Checker version 3.0, a handy set for conservation scientists: A free online Raman spectra database

Pigments Checker is a collection of swatches of historical and modern pigments that offers art professionals, conservation scientists, conservators and fine art photographers, a tool to evaluate and test their imaging and spectroscopic methodologies for pigment identification. "Pigments Checker Free Spectra Database" is an ongoing project to thoroughly characterize each pigment in the collection with a series of spectroscopic and imaging techniques and to make the data open access. This paper presents the free and downloadable database of Raman spectra, adding to the reflectance spectral database already published. The Raman analysis is in agreement with the information provided by the pigments' manufacturers since most of the pigments could be identified by their Raman spectra which were consistent with the expected content reported in literature.