Nature endowed Vigo county with a wealth of natural resources. The mineral resource that has proved of greatest commercial value has been its coal deposits, and for many years Vigo County was the foremost coal-producing county in Indiana. The value of the total product of the mines in Vigo County has mounted to billions of dollars (at current prices), and mining is still being done. Mining in the past, present, and future affects the lives of all citizens of the county, whether or not they are directly involved in mining coal. This report is about the coal industry of Vigo County. Although it is primarily concerned with coal geology, other aspects of the industry are also treated, including the historical developments, engineering problems encountered in mining, environmental problems produced by past mining, and observations concerning the possible course of future events. A summary of the chemical characteristics of coal seams is also included. Because of such a comprehensive treatment it is hoped that the report will prove of interest to a wide audience, not only coal geologists but also residents of Vigo County, land-use planners and government officials, and the coal industry. Besides presenting maps and data relating to past developments and the current status of the coal industry, this report attempts to familiarize the reader with the types of information available from the Indiana Geological Survey and possible uses and limitations of this information. Providing an overview of the coal industry in the county has been emphasized, but persons wishing information on coal resources in particular areas may also find the report useful. Readers requiring more detailed information for their own interpretations are invited to contact the Indiana Geological Survey to obtain original sources of data.