The treatment of a marble statue sculpted by Alexander Doyle on a granite base and erected in New Orleans, Louisiana, in 1884 is described. The statue suffered from sugaring, cracking, microcracking, biological growth, e.g., algal bodies, fungal hyphae, hemi-lichens, and true lichens, which all secrete acidic products damaging to acid-soluble marble, dark sulfation crusts, and loss of original material. Sulfation crusts, which form when sulfur dioxide in the atmosphere reacts with calcium carbonate in the marble to form hydrous calcium sulfate, or gypsum, are particularly problematic in New Orleans due to the presence of catalysts such as carbon, iron, manganese, and vanadium, which are supplied by particulates generated by automobile engines and the burning of fossil fuels. Treatment and literature review focused on a calcium hypochlorite poultice mixed with talc and a slurry mixed with whiting based on HTH Dry Chlorinator, clean bleach, and a registered biocide. Gypsum crests were treated with a poultice of AB57 without EDTA and talc. The consolidant used was H40 Plus Stone Strengthener by ProSoCo, followed by a rinse of methyl ethyl ketone (MEK).