Materials from the earth : rock and mineral products in the Asheville-Buncombe County area

North Carolina Geological Survey Division of Land Resources 1612 Mail Service Center Raleigh, NC 27699-1612 Geologic Note No. 3 http://www.geology.enr.state.nc.us Revised November 2006 MATERIALS FROM THE EARTH Rock and Mineral Products in the Asheville-Buncombe County Area Crushed stone, sand, and field stone are mined in the Asheville area with recent production valued at more than 15 million dollars annually. Crushed stone is necessary for all types of road construction, from driveways to interstate highways, and in any construction that requires the use of concrete. Construction costs are lower where crushed stone is readily available. The Asheville area is fortunate to have an abundant supply of crushed stone. The nation's leading producer, Vulcan Materials, operates a quarry west of Asheville in Enka. Two quarries are operated by Grove Stone and Sand Company; one north of Asheville on the French Broad River near Alexander, and the other east of Asheville near the North Fork of the Swannanoa River between Black Mountain and Swannanoa. The abundance of suitable rock in the Asheville area can yield a reliable supply of this important building material for the future. Two small companies remove sand from river bottom deposits of the French Broad and Swannanoa Rivers. This mineral commodity is also used in the construction industry. Field stone gathered by property owners and stone masons, and quarried by a few independent entrepreneurs, is incorporated into the design of many homes and businesses in the area, providing a truly unique and local architectural element to these buildings. The Civic Center on Haywood Street and the original Grove Park Inn are prominent examples of the use of locally collected stone. Other valuable and useful mineral commodities are produced in the region surrounding Asheville and Buncombe County. Avery County and the Spruce Pine area of Mitchell County lead the nation in the production of feldspar, mica, and ultra-high purity quartz. Much of the feldspar is used in manufacturing glass and ceramics (whiteware). Produced as a co-product, mica is used in cosmetics, paint, plastics, wallboard ("sheetrock"), joint cement, and oil well¬ drilling fluids used to prevent blowouts and gushers. Ultra-high purity, electronic-grade quartz is the other important mineral commodity from the Spruce Pine area. This highly refined, pure quartz product is used in the production of microchips, transistors, and other high-tech electronic devices. Other mineral commodities mined near Asheville include: olivine, a heat-tolerant material used to line industrial furnaces and to make molds for casting metal; and, from the Fletcher area, dolomitic marble used both as ordinary crushed stone and as a durable, white, decorative stone. In the past, other mineral commodities were mined in the Asheville-Buncombe area. These included kaolin, vermiculite, chromite, halloysite, iron ore, gemstones, dimension stone, talc or soapstone, industrial garnet, lime, brick-clay, and gravel. More information on the mineral resources in the Asheville-Buncombe area is available from the North Carolina Geological Survey at 2090 U.S. Highway 70 Swannanoa, NC 28778, telephone: (828) 296-4500.