There was extensive quarrying for Potsdam Sandstone in the Potsdam area , beginning in 1809 .
In the 19th century , Potsdam Sandstone was highly regarded as a building material .
There was extensive quarrying for Potsdam Sandstone in the Potsdam Sandstone area , beginning in 1809 .
In the 19th century , Potsdam Sandstone was highly regarded as a building material .