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 into air. However, in a charcoal fired kiln, the concentration of CO will be much higher than it is in air. Indeed, if all the oxygen in the kiln is consumed in the fire, then the partial pressure of CO in the kiln can be as high as 20 kPa. The table shows that this partial pressure is not achieved until the temperature is nearly 800 °C. For the outgassing of CO from calcium carbonate to happen at an economically useful rate, the equilibrium pressure must significantly exceed the ambient pressure of CO. And for it to happen rapidly, the