The general appearance of the Calhoun Monument was judged to be in relatively good condition except for active corrosion of the bronze sculpture, plaques, and decorative ornamentation. Active corrosion of the bronze was visible by its pale green appearance, streaking, and pitting of the surfaces.
Copper corrosion products of powdery pale green deposits (most likely copper sulfates) and a hard rough-textured crust of matte-black deposits (most likely a mixture of copper sulfides, carbon and other airborne particulate matter). Disfiguring streaking covered 50% of the sculpture which indicates paths where water runs off the sculpture, plaques and decorative ornamentation.
The bronzes appeared to be in fair condition except for several loose and missing bronze pins on the relief plaques located on the lower portion of the monument; a missing bronze letter "O" on the granite plaque; copper lightening protection cable detached from several anchor pins.
Granite portions of the monument were determined to be in good condition except for the general soiling and biological growths; "scaling" in several locations; a 12 in. open crack in the granite radiating from the left foot of the sculpture on top of the monument; most of the mortar and lead joints had failed and this allowed water to enter the structure; three curbing stones had shifted and were out of alignment.