Indiana Caverns the calcium carbonate precipitates out of the water. The calcium carbonate, in the form of the mineral calcite, a solid, crystallizes onto the bottoms and sides of existing stalactites, stalagmites, helictites, and sheets of flowstone to grow the formations over time. Other minerals are brought into the cave by flowing of water to create white, red, tan, and gray colors on the formations and walls. St. Louis Limestone is primarily made of calcite, but is also known to contain magnesium sulfate, manganese dioxide, ferric oxide, gypsum, dolomite, and aragonite. On the show tour, deposits of calcite, manganese dioxide, and ferric
Calcium carbonate Currently calcium carbonate is used to neutralize acidic conditions in both soil and water. Since the 1970s, such "liming" has been practiced on a large scale in Sweden to mitigate acidification and several thousand lakes and streams are limed repeatedly. Calcium carbonate is also used in flue gas desulfurisation applications eliminating harmful SO and NO emissions from coal and other fossil fuels burnt in large fossil fuel power stations. Calcination of limestone using charcoal fires to produce quicklime has been practiced since antiquity by cultures all over the world. The temperature at which limestone yields calcium oxide is usually given