|The Grant Memorial consists of bronze statues on marble bases; although the statues were cleaned, the staining on the marble remains.|
This memorial, dedicated in 1922, consists of a group of bronze sculptures mounted on marble bases. Bronze weathers outdoors if it is not cleaned and waxed regularly. Like stone, bronze dissolves where it is exposed to rainfall, developing a green color and a pitted surface, and it also alters in sheltered areas, with accumulation of a blackened layer. The most notable stone deterioration visible here is the green stain on the marble bases, caused by runoff from the weathered bronze. The green stain does not damage the marble, but it is unattractive, and there are no methods currently available to remove the stain without damaging the marble.
The light-green color on the bronze statues at the Grant Memorial is typical of the way bronze weathers
when it is exposed to acidic rain, the rain dissolves some of the metal and causes staining of the white
Map of All Sites on the Tour [102 K image]