Effects of protective treatments on particle deposition and colour variation in stone surfaces exposed to an urban environment

•Effects of protective coatings during exposure of stone surfaces are investigated.•Properties of deposited particles are analysed on variously treated marble samples.•Cluster analysis and principal component analysis on SEM-EDX data are carried out.•Changes in surface colour are measured on variously treated marble samples.•Different coatings’ susceptibilities to deposition and discolouration are observed.