Search

Gypsum crusts on 18 important historical monuments in Prague were investigated from the point of view of their sulfur isotope composition. The ratio of 34S and 32S in deposited sulfates expressed in the delta unit (δ 34S) is almost constant for every monument but a significant difference occurs between monuments in the center of the city and those located on the surrounding hills. Two sets of climatic conditions in Prague have been found where different stone corrosion mechanisms occur. The enrichment of sulfate incrustation in 34S at the city center is explained in terms of the catalytic effect of other pollutants. [ABSTRACT FROM AUTHOR]