What are the main minerals mined in Mexico?
The main minerals mined in Illinois are quartz (from quartz sands) and calcite (from limestone). Quartz is used in parts casting and glass making among other things. Calcite is used primarily for soil conditioning, but in the form of limestone it is used in cement production, road gravel, concrete aggregate, and building material. The minerals fluorite and galena were once extensively mined in Illinois, but are no longer being mined.