Portland cement is manufactured from some of the earth's most common minerals, limestone and shale. These materials are ground almost as fine as finished cement and moved through a kiln where they are burned at 2800 degrees Farenheit to form a new material called clinker. A small amount of gypsum is blended with the clinker and it is then ground, as fine as face powder, to form cement. Monarch Portland cements conform to ASTM
C-150.

When portland cement, stone, sand and water are mixed together in the proper proportions, the water and cement form a paste that coats every stone and grain of sand and fills the spaces between them. The water triggers a chemical reaction with the cement called hydration. This reaction forms a gel which, as it hardens, binds the stones and sand into a solid mass (concrete) that increases in strength over time.