It is dressed with pietra serena, a grey sandstone local to Florence, which clearly links it to one of the main architectural inspirations for the Wing: the Tuscan church interiors of Filippo Brunelleschi. Unfortunately, the pietra serena elements are extremely porous and appear not to have been properly sealed, and now each pilaster sufferings from greasy dark marks, most likely caused by the public and security staff touching or leaning up against the stone.
DBR Conservation is currently performing a series of cleaning trials with different detergents and poultices to draw out the greasy soiling and discolouration. The success of these trials will inform the cleaning treatments and sealing of the stone in a comprehensive programme when the galleries are next closed this year.
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