9 Ledge - 1550 Level, 1935 - 1989

The Homestake Geology Department Papers consist of 63 boxes of papers, 34 boxes and 2 cabinets of rock specimens, and two boxes and two cabinets of thin sections from the Geology Department at the Homestake Mining Company from 1903 to 2005.

Series 1 James Noble Map Collection was started in 1926 by Dr. Donald H. McLaughlin and James Noble. These maps record the surface geology of the Black Hills down to the 8000 foot level of the mine. The maps cover locations such as the Amicus, B&M, Callendoina, Crown, Ellison, Hidden Fortune, Independence, Lone Stare, Millikan, Old Abe, Oro Hondo, Pierce, Ross, and Yates shafts. The geology maps mark in detail all available drifts and crosscuts. These maps were used to update larger maps found in the Homestake Mining Company Map Collection.

Series 2 Noble and Harder Research and Notes contains research, notes, reports, and data on the rock samples collected during the 1930s and 1940s.

Series 3 Files from the Chief Geologist Office contains various papers such as reports, correspondence, and notes that were filed in the Chief Geologists Office from 1903 to 2000. These documents represent all of the operations that occurred in the Geology Department.

Series 4 Exploration Division Papers contain geochemical data such as assay results, petrography reports, photographs, negatives, slides, reports, and other documents related to the projects done by the Exploration Division to find more ore to mine from 1945 to 1999.

Series 5 Diamond Drilling Documentation contains reports, priorities, schedules, drawings, indexes, logs, and other documents related to Diamond Drilling from 1918 to 2001.

Series 6 Back Sample Stope Sections contain stope section drawings, with sample locations marked which were then provided to the Mine Department for use, guidance, and to prepare other maps in the Mine Department from the 1940s to 1992.

Series 7 Estimated Inventory Ledgers contain changes to Stope Master File Forms, Ore Block Estimate Forms, copies of maps where the samples are from, and calculation notes used to calculate the ore reserves of the Homestake Mining Company from 1974 to 1995.

Series 8 Geology Samples contain specimen indexes, identification cards, and rock samples for the Northern Black Hills Collection, the Southern Black Hills Collection, Rochford Specimen Collection, the Homestake Specimen Collection (New Series), the first Homestake Specimen Collection (Old) collected by Donald McLaughin and two others is noted to be at Harvard University, and other various rock samples. Some of the samples from the listed collections can be found in the 5029 Tom and Melissa Campbell Collection.

Series 9 Thin Sections contain thin and polished sections that are related to the rock samples from series 8. There is a printout of the Thin Section Library in the Research Library file cabinet drawer 1 with two floppy disks.