Source: Marmoles la Profecia, Durango, Mexico
By Don Marsh
Mexico-based Marmoles la Profecia is introducing to its northern neighbors a high-grade marble aggregate for wet- or dry-cast concrete mix designs, along with a polishing process that yields block, pavers and precast or cast-in-place surfaces mimicking terrazzo. The company derives recrystallized marble (calcium carbonate) from a quarry in the north-central state of Durango. Deposits suggest a range of 20 colored rock, sufficient to replace pigments for certain manufactured concrete products or cast-in-place slabs or structures. La Profecia is seeking to establish production and distribution through U.S. or Canadian aggregate producers, or other companies with crushing equipment. Rail shipment of 10- to 12-in. marble eases border-security transfer and ensures finished aggregate purity and quality.
A three-step method creates the terrazzo appearance in a Marmoles marble-bearing concrete matrix: smoothing, where a few millimeters are removed from the surface to impart porosity; densifying, where an agent penetrates and seals the pores, while imparting durability and abrasion resistance; and, machine polishing and shining with different grades of finishing stones. The method especially suits masonry and precast production environments, La Profecia officials note, as it can be performed on a small scale and without the high volume of water and cement consumed in conventional terrazzo finishing. The company announced the North American availability of its recrystallized marble at the National Concrete Masonry Association's 2010 Icon Expo, San Antonio, conferring with major and independent producers on the rock and finishing methods. Û Fernando Salinas, firstname.lastname@example.org