Along the shore of Amana, Iowa's lily pond there are fragments of fill material. The former wetlands depression was made into a pond when the mill run was dug many years ago to provide water power to the society's woolen mill. Among the fill material exposed is this brick and mortar material from an unknown source. Most likely the bricks can be matched locally to buildings in Amana and therefore a date can be established. If you are looking for some detective work - here's a project for you.