2017 Minerals Yearbook FELDSPAR AND NEPHELINE SYENITE [ADVANCE RELEASE] U.S. Department of the Interior June 2020 U.S. Geological Survey Feldspar and Nepheline Syenite By Zachary T. Ghalayini Domestic survey data and tables were prepared by Raymond I. Eldridge III, statistical assistant. In 2017, feldspar production in the United States was from the U.S. Department of Labor’s Mine Safety and Health estimated to be 440,000 metric tons (t) valued at $27.8 million, a Administration. Of the seven companies that produced feldspar, 6% decrease in quantity and a 16% decrease in value compared five responded to the canvass, representing about 40% of the with those of 2016 (table 1). Exports of feldspar in 2017 2017 production tonnages listed in tables 1 and 2. decreased by 9% to 5,340 t, valued at $1.21 million, and imports Feldspar was mined in six States (table 3). North Carolina of feldspar were 290,000 t, valued at $7.51 million, nearly eight was by far the leading producer State; the remaining five were, times the quantity imported in 2016 (tables 5, 6). The dramatic in descending order of estimated output, Virginia, California, increase in imports of feldspar was the result of increased Idaho, South Dakota, and Oklahoma. Production was from imports from Turkey, as reported by the U.S. Census Bureau. 10 mines and beneficiating facilities—4 in North Carolina, Imports of nepheline syenite (predominantly from Canada) 2 in California, and 1 in each of the four remaining States (table 3). more than doubled to 1.46 million metric tons (Mt) valued at I-Minerals Inc. announced in May that the Idaho Department $88.4 million. Increased imports resulted in apparent domestic of Lands had approved the mine permitting process for consumption doubling in 2017. World production of feldspar in its Helmer-Bovill project in north-central Idaho; the mine 2017 was 24.7 Mt (tables 1, 7). would produce potassium feldspar, halloysite, kaolin, and Feldspars, which constitute about 60% of the earth’s crust, quartz (I-Minerals Inc., 2017b). In 2016, pilot plant work by are anhydrous aluminosilicate minerals of two main groupings: an independent laboratory resulted in a potassium feldspar potassium- to sodium-alkali feldspars and sodium- to calcium- product with 13% to 14% potassium oxide (K2O) and low plagioclase feldspars. The alkali feldspars mostly are used iron [0.03% ferric oxide (Fe2O3)] content (I-Minerals Inc., in glassmaking and ceramics, and the plagioclase feldspars, 2017a). The company produced small quantities of feldspathic especially the sodium-rich varieties, are mainly used in ceramics (feldspar-quartz) sands from its WBL Tailings resource area, and various construction applications. Plagioclase of higher which was adjacent to the Helmer-Bovill property, for use in calcium content is used for its alumina content across multiple the production of ceramic tiles. The WBL Tailings are feldspar- construction products, such as fiberglass or for the strengthening and quartz-rich materials that were left on the property from of glass-reinforced plastic products. In a broader sense, by 1960 to 1974 by the former mine operator, who then focused on volume, much of the sand and gravel used as aggregate in kaolin production from the ores. I-Minerals’ reclamation mining concrete and asphalt is composed of plagioclase, and plagioclase permit allows it to mine about 45,000 metric tons per year (t/yr) is an important constituent of some building stones. Nepheline of feldspathic sand from the WBL Tailings between June and syenite is an essentially quartz-free igneous rock composed of October of each year through 2022. Feldspar-quartz sand from alkali feldspars and nepheline, which is a feldspathoid mineral the WBL Tailings was sold to Quarry Tile Co.’s tile plant that forms in place of alkali feldspars because the magma (melt) in Spokane, WA. In addition to providing a revenue stream, was deficient in silica. Nepheline syenite has many uses similar the sale of sands from WBL reduced the tailings storage to those of alkali feldspar. requirements for the company (I-Minerals Inc., 2014). WBL United States apparent consumption of domestic and imported Tailings was one of three mineral-resource areas on the Helmer- feldspar and imported nepheline syenite from Canada combined Bovill property, a multimineral project from which the company was more than 2 Mt, primarily in ceramics and glass production expected production of 47,000 t/yr of potassium feldspar during for use in the construction industry and glass for use in the a projected 25-year mine life (I-Minerals Inc., 2016). automotive sector; both also were used as filler in various Consumption.—In 2017, approximately 66% of domestic products, such as paints and coatings (tables 1, 4). Domestic feldspar sold or used was consumed in the manufacture of feldspar production data include feldspar-quartz mixtures from glass, including glass containers, flat glass, specialty glass, and silica producers and aplite (a rock with quartz and feldspar as fiberglass for home insulation; feldspar use for glass increased the dominant minerals) from one producer. Domestic nepheline by about 3% (table 4). In glassmaking, feldspar promotes the syenite production primarily was used in the production of mixing of the melt components by fluxing (reducing the melt roofing granules, but it was also used in the production of viscosity and the melting temperature) the system. The alkalis ceramic and porcelain tiles and other construction applications. in feldspar (especially potassium and sodium ions) lower the melting temperature within the mix and promote the melting of Feldspar and chemical bonding of the other glass batch minerals, such as quartz, to produce glass. Alumina and calcium ions in feldspar Production.—Data on domestic production, sales, and impart increased resistance to physical and chemical breakdown use of feldspar in this chapter were collected by the U.S. of the glass product. Geological Survey (USGS) using responses from voluntary Much of the remaining feldspar consumption was in the surveys. Production for nonreporting operations was estimated manufacture of ceramics, including ceramic and porcelain by using previous years’ submissions and worker-hour reports FELDSPAR AND NEPHELINE SYENITE—2017 [ADVANCE RELEASE] 24.1 tile, electrical insulators, sanitaryware, and tableware. In World Review.—More than 70 countries had significant ceramics, as in glassmaking, the alkalis (calcium, potassium, resources of feldspar and more than 40 produced feldspar in and sodium) in feldspar act as a flux, working with soda ash to 2017; world production was 24.7 Mt. The leading feldspar- lower the melting temperature of the mixture while increasing producing countries in 2017 were Turkey, China, and Italy, the fusibility of the batch materials. Feldspar also controls the followed by India, Thailand, and Iran, in descending order of degree of vitrification of the ceramic body during firing. Smaller production (table 7). quantities of feldspar are used as fillers and extenders in paint, As in the United States, feldspar consumption worldwide plastics, and rubber. was mostly for glassware and ceramics. Global ceramic tile The construction industry was a significant consumer of production, about 50% of which was for floor tile, increased glass and ceramic products, particularly for windows, flooring, slightly to nearly 13.6 billion square meters, with the most and sanitaryware. In the United States, construction starts for substantial increase in Africa (Biraldi, 2018a, p. 58, 60). China, new private housing increased slightly to 1.20 million units in the world’s leading tile producer, accounted for 47% of world 2017, up from 1.17 million units in 2016. This upward trend production, and India and Brazil ranked second and third, has continued since 2010. The 2017 housing starts, however, respectively, the former with a 13% increase in production remained lower than those of many of the years from 1959 and the latter with a slight decrease. Ceramic tile production through 2007 (U.S. Census Bureau, 2018b). The value of total increased most notably in Egypt (by 20%), Vietnam (by 16%), construction put in place, which uses significant quantities India (by 13%), and Iran (by 10%). Global consumption of of flat glass and ceramic tile products, increased for the sixth ceramic tile increased slightly to 13.3 billion square meters. consecutive year, up by 4.5% to nearly $1.25 trillion in 2017 China, the world’s leading ceramic tile consumer, accounted for from $1.19 trillion in 2016, both having surpassed the previous 41% of world consumption, and India and Brazil ranked second peak of $1.16 trillion in 2006 (U.S. Census Bureau, 2018a). and third, respectively (Biraldi, 2018a, p. 62, 64). In 2017, the United States became the leading importer of China continued to be the leading exporter of tile with 33% ceramic and porcelain tiles, which accounted for nearly 71.4% of world exports, although exports from China decreased for of domestic tile consumption; the four leading suppliers were the fourth consecutive year. Spain ranked second, accounting China (30%), Mexico (18%), Italy (18%), and Spain (13%). for 15% of global tile exports, and Italy was third with 12% Exports of tile in 2017 decreased by 21%, with the majority of exports. Exports from Spain and Italy increased by 3% going to Canada (75%) and Mexico (8%) (Whitmire, 2018). and slightly, respectively, and exports, in descending order of Porcelain tile, which is less porous than ceramic tile, increase, from India, Iran, and Turkey increased significantly increasingly was becoming the tile of choice in the United States; (Biraldi, 2018a, p. 66). the majority of U.S. imports of flooring tiles in 2017 were China.—Feldspar was mined in the eastern and southeastern porcelain rather than ceramic. In 2016, Dallas-based Dal-Tile Provinces of China, and national production was estimated Corp.