Figures & data
Figure 1. Cleaning outcomes at a portal of the northern transept: the sculptures were cleaned with Nd:YAG Q-switched laser devices, while airbrasive techniques were performed on architectural background elements and tiny areas of the sculptures where polychromy relicts were found: here on the eye of this standing figure. After CitationVergès-Belmin et al. (2014a). (A) Overview; (B and C) details of Balaam's face; (D) sampling location of sample illustrated on (E) and (F) images; (E) top view bulk sample (binocular lens); (F) polished cross section, SEM-BSE image: (1) calcium carbonate substrate, (2) calcium oxalate layer, (3) calcium sulphate remnant.
Figure 2. Overview of the portals at the southern transept. Test area on the left jamb of the central portal, and top view of the centimeter-size sample cleaned with short free-running (SFR) and long Q-switched (LQS) modes.
Figure 3. Test area C on Berchères limestone: general aspect of 2002 cleaning windows (QS and microsand-blasting), and 2012 cleaning windows (LQS and SFR).
Figure 4. General appearance of cleaning areas SFR (A) and LQS (B) on Paris limestone (test area B).
Figure 5. Results of the colour measurements on areas (zones) A and C.
Figure 6. SEM-BSE image, cross section, uncleaned area. EDS results: Layer 1: Ca, C, and O: calcium carbonate; Layer 2: Ca, C, and O: calcium oxalate ; Layer 3: Ca, S, and O: calcium sulphate.
Figure 7. SEM-BSE image, cross section, uncleaned area. EDS analytical results: Layer 1: Ca, C, and O: calcium carbonate; Layer 2: Ca, C, and O: calcium oxalate; Layer 3: Ca, S, and O: calcium sulphate.
