The advantages of using portable Raman spectrometer equipment, such as avoiding sampling and providing a higher number of results, are contrasted with some of its shortfalls that make other analytical techniques necessary to characterize salt efflorescences on historic buildings. In-situ analyses of salt efflorescences were carried out with a portable Raman at both the so-called "Silk Tomb" and "Monastery" rock-cut fa̧ades at the Archaeological Park of Petra (Jordan). Samples were also taken to be analyzed in the laboratory with X-ray diffraction (XRD) and Environmental Scanning Electron Microscope with Energy-Dispersive X-ray spectroscopy and Cathodoluminescence (ESEM-EDS-CL). This research shows the pros and cons of these analytical techniques-and how they complement each other-to identify the occurrence and determine the origin of soluble salts, which are deeply damaging these rock-cut monuments by salt crystallization processes.
Bibliographical noteFunding Information:
The authors acknowledge the financial support of PCI-AECID (A/025170/09), GEOMATERIALES (S2009/MAT-1629), CONSOLIDER-TCP (CSD2007-0058), and JAE CSIC Programme (PL). The authors thank L. Tormo, A. J. García, and M. Furió (MNCN, CSIC) for technical support with ESEM-EDS-CL analyses and I. Serrano for technical support with XRD analyses. Special thanks go to Eng. Fawwaz R. Ishakat, from Hashemite University (Jordan), without whose help this work would not have been possible.
- Nondestructive testing
- Portable Raman
- Salt efflorescence
- Stone decay