Fig. 5From: A combination of invasive and non-invasive techniques for the study of the palette and painting structure of a copy of Raphael's Transfiguration of ChristPigment identification in the RF-2 sample. Blue color. a Microphotograph of the cross section under visible light; b Smalt SEM–EDX spectrum c Lapis lazuli SEM–EDX spectrum; d Raman spectrum of blue particle (lapis lazuli)Back to article page