Chile's Cementos Polpaico is engaged in the manufacture and supply of cement. It is the largest cement producer in the country with installed capacity of 2.7Mt/y. Its products and services include on-site ready-mix concrete supply; construction aggregates, such as crushed stone, sand and gravel; and on-site technical assistance. Its Cerro Blanco plant is in the metropolitan region, and it has plants in the northern town of Mejillones and Coronel in the south. Polpaico is controlled by Swiss group Holcim and has roughly one-third of the Chilean cement market.