This study assesses indicative technical correspondences and divergences between Francisco de Zurbarán’s painting practices and those observed in the seventeenth-century Óbidos workshop (Baltazar Gomes Figueira and Josefa d’Óbidos). We focus on the composition and function of priming layers, the shadow-to-light painting sequence, and pigment/binder usage. A multi-analytical approach was employed: portable X-ray Fluorescence (XRF), Optical Microscopy on polished cross-sections (OM), Scanning Electron Microscopy in backscattered mode with Energy-Dispersive X-ray analysis (SEM-BSE/EDS), Micro-Confocal Raman Spectroscopy (µ-Raman), and Micro-Fourier Transform Infrared Spectroscopy (µ-FTIR). Rather than treating single pigments as diagnostic, we compare patterns of application and stratigraphic behaviour—notably a two-layer priming, in which a finer, Fe-rich upper layer is actively used to build shadows, and a consistent exploitation of the priming as a value layer in a shadow-to-light sequence. Materials largely overlap, while priming compositions differ, plausibly reflecting local resources. Given the small corpus (two works by Zurbarán, one by Baltazar, and one by Josefa), conclusions are presented as indicative and contextualized within Iberian workshop practice.
Antunes et al. (Mon,) studied this question.