The Merchants’ Exchange Building stands on a triangular plot of land in Independence National Historical Park, Philadelphia, PA.  Designed by Philadelphia architect William Strickland in 1831, the building was completed in 1834 and served as a center of commerce and Post Office for the city until 1900.  After numerous changes of use, the National Park Service purchased the Merchants’ Exchange in 1952 and continues to use the building as office space. The Merchants’ Exchange was designated a National Historic Landmark in 2001.

Conservation of the twelve Carrara marble capitals and six (6) Carrara marble pilasters included cleaning with LASER and IBIX micro-abrasive methods; consolidation of the stone; mechanically pinning spalling stone; and reintegrating stone using repair mortar. The eighty (80) Pennsylvania Blue Marble antefixes were transported to our conservation studio for treatment, which included cleaning, consolidation, grouting, pinning of broken stone, and Jahn restoration mortar fills. The Pennsylvania Blue Marble facades were also grouted, consolidated, and pinned. The sheet copper cupola (stamped S. Yellin 1964) was non-destructively (ultrasonic) tested to assess potential loss of thickness. The weather vane was cleaned and gilded in-situ. All aspects of the project were thoroughly documented through photography and AutoCAD drawings. This project won a Construction Project Award from Preservation Pennsylvania in 2015.