Abstract The three orefields in the English Pennines contain strata-controlled epigenetic deposits of lead, zinc, fluorine, barium minerals. They are localized in favorable shelf-facies Carboniferous sediments, resting on basement "highs" and gently domed. Lateral zonation of minerals is strikingly developed, in part, possibly wholly, controlled by falling temperature, which according to fluid inclusions measurements by F. J. Sawkins reached over 200° C at the focal centers. Hot juvenile solutions are considered to have been involved; possible mixing with connate brines is noted and the possibility of deriving some elements by leaching of wall-rocks is examined.

Abstract The Illinois-Kentucky Fluorspar District encompasses an area in excess of 2,500 km 2 in southern Illinois and western Kentucky (Fig. 1) and has been the most productive fluorspar mining area in the United States since 1870. The development of the district began in 1835 when several small lead mining enterprises were started in both Illinois and Kentucky. It was not until the 1870’s that fluorspar from the district became a commercial product and by the turn of the century, it had become a significant component in the national economy, spurring exploration and mining in the region. The resource demands of the nation during World War II led to frenzied activity in the region, with a record production of 280,510 mt/a (metric tons per annum) of fluorspar concentrates in 1943. Based on U.S. Bureau of Mines records, published data (Grogan and Bradbury, 1968), and confidential company records, more than 12 million mt of fluorspar concentrates have been shipped from the district since 1870. Estimating the production of zinc, lead and barium mineral concentrates is problematic because of a lack of accurate records, but at least several hundred thousand metric tons of these products are likely to have been shipped since 1835.