Abstract: | We present the first depth profiling on a polished cross‐section carried out by micro‐Raman spectroscopy aimed at investigating the penetration depth of an inorganic protective material (ammonium oxalate) applied on carbonatic surfaces (ancient plaster) and to detect the distribution of mineralogical phases inside the material. The reason for such a Rapid Communication is the importance of our study for the field of conservation, in which at present the treatment with oxalates is a hot issue. Copyright © 2008 John Wiley & Sons, Ltd. |