The White Marble of the Arch of Augustus (Susa, North-Western Italy): Mineralogical and Petrographic Analysis for the Definition of its Origin

A multi-analytical study confirms that the white marble used in the construction of the Arch of Augustus in Susa, northwestern Italy, originates from the Foresto marble, part of the metamorphosed carbonate cover of the Dora Maira Massif. This finding challenges the long-standing assumption that the marble was locally extracted. The research employed petrographic analysis (including optical and scanning electron microscopy), electron microprobe analysis, and stable isotope analyses to compare samples from the arch with reference materials. The results suggest that the choice of Foresto marble was likely driven by economic factors and the political interests of the ruling family of the Alpes Cottiae, who sought to promote a local marble despite its non-local origin.

Agostoni, A., Barello, F., Borghi, A., & Compagnoni, R. (2016). The White Marble of the Arch of Augustus (Susa, North-Western Italy): Mineralogical and Petrographic Analysis for the Definition of its Origin. Archaeometry, 59(3), 395–416. Portico. https://doi.org/10.1111/arcm.12251