Although the United Kingdom had comparatively few mineral resources (except for North Sea oil), it was a significant player in the world mining and mineral-processing industries, because of the extensive range of UK companies that had interests in the international mineral industry. An organized coal-mining industry has been in existence for over 300 years—200 years longer than in any other country—and has traditionally been by far the most important mineral industry. Mine production of ferrous and nonferrous metals has been declining for more than 20 years, as reserves became depleted, necessitating imports for the large and important metal processing industry. Metals, chemicals, coal, and petroleum were among the country's leading industries in 2002, and fuels and chemicals ranked second and third, respectively, among export commodities. In 2000, mining production was 45% higher than in 1990. The industrial minerals sector has provided a significant base for expanding the extractive industries, and companies had a substantial interest in the production of domestic and foreign aggregates, ball clay, kaolin (china clay), and gypsum. The United Kingdom was a leading world producer and exporter of ball clay and kaolin; operations were mainly in Dorsetshire and Devonshire.
Other minerals extracted in 2000 included gravel and sand (common and industrial), 102.5 million tons; crushed limestone, 86 million tons; crushed dolomite, 14 million tons, down from 18.3 million tons in 1997; crushed igneous rock, 50 million tons; kaolin (dry weight sales), 2.42 million tons; ball and pottery clay (dry weight sales), 1 million tons, up from 866,000 in 1996; potash, 500,000 tons, down from 608,400 in 1998; dimension sandstone, 300,000 tons; gypsum and anhydrite, 1.5 million tons, down from 2 million tons in 1998; fluorspar (two-thirds acid grade), 35,000 tons, down from 65,000 tons in 1998; and crushed chalk, 10 million tons. Lead and hematite iron ore were worked on a small scale; the output of iron ore (gross weight) dropped from 916,000 tons in 1980, to 1,033 in 2000. Alumina was produced from imported bauxite. The United Kingdom's last commercial tin mine, South Crofty, in Cornwall, closed in 1998, was sold, and aimed to reopen in 2001—its capacity was 1.8 million tons per year. A small tin mining operation produced cassiterite for tourist jewelry and ornaments. Zinc and tungsten were no longer mined. In 2000, the United Kingdom also produced barite and witherite, bromine, hydraulic cement, clays (including fire clay, fuller's earth, and shale), feldspar (china stone), quicklime and hydrated lime, nitrogen, rock and brine salt, sodium compounds, slate, sulfur, pyrophyllite and soapstone talc, and titania. Most slate mining was in northern Wales, and the Penrhyn quarry, at Bethesda, was considered the world's largest, and has been in operation for more than 400 years. No calcite stone was produced in 1999 and 2000.
Most nonfuel mineral rights in the United Kingdom were privately owned, except gold and silver, the rights to which were vested in the royal family and were known as Crown Rights. Onshore exploration activities were to be directed mainly toward precious metals, mainly gold. In Northern Ireland, the rights to license and to work minerals were vested in the state.