This 19th century marble bust portraying the Emperor Tiberius is one of a group of six marble sculptures that came to WAAC from Bowdoin College.  The marbles had undergone a high moisture event, resulting in mold contamination and surface staining.  The sculptures underwent emergency mold remediation at the College's art museum before they traveled to WAAC for further cleaning and stain reduction.

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After a thorough cleaning with brushes, soft sponges, and a HEPA-filtered vacuum, the sculptures were cleaned overall to reduce the staining left behind by the mold.  A low percentage solution of tri-ammonium citrate in deionized water, adjusted to a pH of 9 to limit the effect of the chelator on the marble surface, was used overall.  It was applied to the surface with cotton swabs and small cotton pads that were left on the surface for short periods of time where the staining and grime were heavier.  The solution was cleared from the surface with deionized water adjusted to a pH of 9, with the addition of marble dust.

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This particular sculpture also had a moderate to heavy layer of grime on the surface.  The citrate solution was effective at removing the grime layer and the yellow-brown staining left behind from the mold.