Every Californian uses about 5-7 tons per year of aggregates for housing, roads and highways, office buildings, schools, shopping centers, public infrastructure, and in a vast array of consumer, industrial, and agricultural products. Aggregates are essential to daily living, and although few of us think about it, we depend upon consistent and uninterrupted aggregate supplies as much as we expect electricity and water.
Aggregates are sand, gravel, and crushed stone. Over 90% are used in construction, since aggregates are necessary for making concrete and asphalt. In fact, aggregates comprise 70-80% of concrete, and about 95% of asphalt mixtures. Without aggregates we wouldn't have homes, highways, hospitals, buildings, airports, or any other structure used by Californians. The construction of an average home, including necessary neighborhood infrastructure, requires nearly 400 tons of aggregates. Approximately 60% of all aggregates are used in public works projects, and nearly 90% of all materials required to build federal, state, and local roads consists of sand, gravel, and stone. Using conservative population estimates for the next 20 years, Californians will require 5 billion tons of aggregates, or an average of 250 million tons per year. Aggregates are both a major contributor to, and key indicator of, the economic health of a region
California's diverse geography and geology uniquely situate us to have varied and abundant source of minerals. The industrial minerals found in California include limestone, clay, industrial sands, pumice, borates, diatomaceous earth, and rare earth minerals. Less common than aggregates, they are every bit as important to our daily lives, economic vitality, and environmental quality.
Their uses include glass-making, nutritional supplements for livestock and farmlands, cement, vitamins, bricks, pipe for our water systems, roofing materials, glass-making, home insulation, wall-board, cleaning materials for porcelin and tile, water and air filtration systems, energy-saving light bulbs, scientific tools, fiber optics, environmentally friendly paper, paints, golf courses, athletic fields, and even cat-litter... the list goes on and on...
Industrial minerals play several important roles for California. Regional sources of limestone, gypsum, and industrial sands are important to ensure California has nearby sources of nutrients for farmlands and livestock and to support glass manufacture and other manufacturing industries related to agriculture. In-state sources of clays, gypsum, and roofing aggregates help ensure the availability of local materials for manufacture of wallboard, roofing, and other construction needs. Limestone sources assure local supplies for critical cement production. Other unique minerals, such as rare earth elements, make California a leader in providing minerals for technologies to make energy-efficient light bulbs, hybrid car motors, windmills, and many other technology applications, including magnets, batteries, lasers, catalysts, and superconductors.
Limestone fact sheet: Limestone: One of the Most Versatile and Widely Used Minerals in the World
California's ready mixed concrete producers are suppliers of an essential and remarkable building material – in fact, the most widely used man-made material in the world. Concrete is a remarkable material because it is at once plastic – can be molded into any shape – and becomes strong and durable when finished. These qualities explain why one material – concrete – can build skyscrapers, bridges, sidewalks, superhighways, houses and dams.
Concrete is made from rock, sand, water, and cement (or cement substitutes, such as fly ash, slag, or natural pozzolans). The ingredients in ready mixed concrete are batched into a mixer truck at a central plant and then transported to a construction site. The concrete has to be poured within 90 minutes of being batched.
Concrete has become a key element in meeting California's environmental goals, since concrete homes and buildings are energy efficient and can be produced from local materials and often with recyclable materials. Specific types of concrete and uses can also meet a variety of societal goals, such as concrete mixed with recycled aggregates, water, or cement substitutes (such as recycled fly ash, slag, and natural pozzolans). Specific types of concrete, such as pervious concrete used in pavements, can reduce water runoff, which helps society achieve water quality goals. It is not surprising then that concrete is increasingly requested to meet the building requirements for Leadership in Energy and Environmental Design (LEED).
For a list of CalCIMA members, go the "Members" page.