The existence of underlying structures in an x-radiograph of La Miséreuse accroupie (1902), a Blue Period painting in the collection of the Art Gallery of Ontario (AGO), prompted a comprehensive technical study to unpack how Picasso actually made this iconic work of art. A methodology was used in which 2D macroscopic data were collected in situ using fiber optics reflectance spectroscopy and macro-X-ray fluorescence mapping. It confirmed that Picasso painted over an earlier composition. It also revealed, between the former composition and the finished work, an earlier version of the crouching woman painted by Picasso. The preliminary pigments distribution obtained from both hidden and visible compositions guided the sampling of micro-fragments to perform supplementary micro-analyses. Analyses at the microscale allowed the identification of the different pigments present in the complex stratigraphy of the painting. Scanning Electron Microscopy, Fourier Transform spectroscopies and 2D micro X-Ray Powder diffraction provided further insights into Picasso's early palette.

Picasso reused the canvas of Mother and Child by the Sea (1902) several times. A hyperspectral near-Infrared (960-1680 nm) reflectance imaging survey of the painting revealed newsprint text from