This paper presents the results of a technical investigation of two panel paintings
from the collection of the Suermondt-Ludwig-Museum, Aachen, formerly attributed to a Burgundian workshop and more recently to an unknown Spanish workshop. The study applied methods
of noninvasive analysis that aimed to understand the painting process and the conservation history
and to reevaluate the attribution of the panels. Noninvasive analysis was carried out using stereomicroscopy, ultraviolet fluorescence, raking light topographical studies, X-radiography, infrared reflectography, and portable X-ray fluorescence. Microsamples were taken for examination of layers
and material analysis using scanning electron microscopy–energy dispersive X-ray spectroscopy and
Fourier transform infrared spectroscopy. The results of the technical study informed both the attribution of the works to the Kingdom of Aragon, Catalonia, or the Province of Valencia and decisions
for the conservation treatment of the panels. The study also corroborated that the paintings are
remnants of a much larger unknown altarpiece. At present, no workshop attribution can be established, but it is clear that the paintings are characteristic of a small group of master artists-craftsmen
practicing at the end of the fifteenth century.