America's portland cement industry began in the Lehigh Valley. The rich deposit of limestone known as the Jacksonburg Formation arcs through the valley from Berks County, Pennsylvania, to Warren County, New Jersey, and today it still provides the raw material for the Lehigh district's famous high-quality portland cement. Cement from the Lehigh Valley built America's skyscrapers, dams, and highways. The Lehigh Valley Cement Industry documents not only...