Fig. 7From: In-situ multi-analytical characterization of original and decay materials from unique wall mirrors in the House of Gilded Cupids, PompeiiRaman spectra collected from the crusts detected on Mirror 1. White crusts (a) are composed of calcium sulphate, which often display the additional presence of nitrocalcite. The yellow crust (b) is composed of a mixture of calcium sulphate and goethiteBack to article page