Fig. 4

Top left: Afternoon in Spring at Neuchâtel (WA.RS.ED.298.a). Top right: macro-XRF maps of copper (blue) and arsenic (red). Bottom: XRD diffractogram of a greenish area, the asterisks indicate peaks from the paper support

Top left: Afternoon in Spring at Neuchâtel (WA.RS.ED.298.a). Top right: macro-XRF maps of copper (blue) and arsenic (red). Bottom: XRD diffractogram of a greenish area, the asterisks indicate peaks from the paper support