Fig. 22From: Exfoliation of stone cultural relics under the microclimate in the Yongling Mausoleum of the Former Shu DynastyPhase diagram for the system Na2SO4-H2O in a plot of relative humidity versus temperature. The continuous lines indicate the boundaries of the stable phases. The discontinuous line corresponds to a solution in metastable equilibrium with respect to thenardite and supersaturated with respect to mirabilite [41]Back to article page