Hummelstown brownstone is a medium-grain, dense sandstone quarried near Hummelstown in Dauphin County, Pennsylvania, USA. It is a dark brownstone with reddish to purplish hues, and was once widely used as a building stone in the United States. Hummelstown brownstone and similar sandstones were known as “freestone” because of properties allowing them to be worked freely in every direction, rather than in one direction along a “grain”. This characteristic made them very popular with stone cutters and masons.