Digital flight line data for a high-resolution horizontal magnetic gradient and radiometric survey over an area of southeast Missouri and western Illinois. Data are provided in CSV and GeoTiff formats.

Sample locations, location descriptions, lithology, mineralogy, and geochronological relationships of drill holes that penetrated the buried Precambrian basement in this area. Detailed well log and cutting descriptions are included if available. Data are provided in Microsoft Access and tab-delimited text formats.

Age dating of apatite and rutile samples from the iron oxide-apatite-rare earth element and iron oxide-copper-gold deposits hosted by the Mesoproterozoic rocks in this area. Data are provided in Microsoft Excel and CSV formats.

Chemistry and geologic information for nearly 30,000 historic ore and ore-related rock samples from mineral deposits and mining districts in the United States. Data are provided in Microsoft Access and CSV formats.