Korner grave in section B at Prospect Hill Cemetery in Washington, D.C., in the United States in 2014. Prospect Hill Cemetery was added to the Register of Historic Places of the District of Columbia (a listing of historic sites maintained by the city) in 2005. Both limestone and granite were used for grave markers in the mid-Atlantic region. This is a funerary practice common only to this region. Limestone is a soft stone which is easily carved, but it also weathers swiftly and deteriorates. Note the butterfly symbol on the marker, a common Christian image denoting belief in resurrection.