Geography of Illinois before the dinosaurs. Galena, a lead ore, has been mined in the northwest corner of the state. The ore was processed around Peru, Illinois, where river transport was available to bring the ore to a source of coal. About six tons of coal are needed for each ton of ore. Fluorite, calcium fluoride, is the state mineral. It is mined in the southeastern portion of the state, around Metropolis. Fluorine gas is produced from fluorite. This is used in the production of uranium hexafluoride in Metropolis, Illinois for use at the gaseous diffusion plant in Paducah, Kentucky. Geodes can be
Ore shoot for hundreds or thousands of feet horizontally and vertically. Such a structure could contain an area of enhanced metal content extending horizontally and vertically. This would be termed an "ore shoot." The existence of the ore shoot could be recognized visually in a tunnel or "drift" excavated along the structure, or by the assaying of rock samples cut from the walls and roof of the tunnel. Ore shoot In mining and geology, an ore shoot is a long seam of mineral or metal bearing rock that can be profitable to extract. The term may have originated in the 17th and