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IdentiJying the source area of white marbles has long been a problem in archaeology. To address this problem, about I000 samples,from known Classical quarrying areas in Greece, Italy and Turkey were analysed using cathodoluminescence. Twenty-one cathodomicrofacies were recognized, each qf which generally characterizes a given area. In cases where the cathodomicrofacies is common to more than one area, di3C and aiRO signatures prouide an effective complementary dataset which allows additional distinctions. Determination keys for the 21 cathodomicrofacies observed are proposed based upon their principal cathodoluminescence colour, and their stable isotopic signature. Plate 1 Barhin et al. (see text for detailed caption) [Facing page 174 Platc 2 Burbin et al (we t e x / for cterurled caption)

Black crust growth mechanisms on three French building stones are described using diagenetic models that reveal the close links between the crust–stone interfaces and the microfacies of the host limestone. Each limestone is representative of a specific sedimentary facies and displays mixed pore structure: crinoidal limestone (Euville limestone), oolitic limestone (Savonnières limestone) and bioclastic matrix-supported limestone (Courville limestone). The crinoidal limestone is mainly made of well-developed calcitic cement (spar syntaxial calcite) with low macrocroporosity (15–20 vol. %). The oolitic limestone is macroporous (30–40 vol. %), oolite nucleus being partially or completely dissolved. The third building stone studied is less porous (14 vol. %) but presents a significant microporosity.Weathering of the Euville limestone proceeds primarily through preferential exploitation of cleavages and microcracks and secondly by progressive recrystallization in the areas separated by previous gypsum fill-in (micro-box work). In the Savonnières limestone (oolitic limestone), gypsum recrystallization could occur without microcracks: elements are sometimes nearly totally weathered, while the palisadic calcitic cement surrounding the oolites was still preserved. In the matrix-supported limestone (Courville limestone), weathering could deeply affect the matrix while elements are not weathered. When a layer of microcrystalline calcite is observed on the surface of the limestone, however, the black crust growth seems to be limited to the external part of the stone.Porous characteristics of limestones directly depend on sedimentary and diagenetic phases developed. The pore network controls moisture movement and also determines the reactivity of the stone to gypsum recrystallization.