Hi Marty, There is a volunteer in Harney Co. listed at Random Acts Genealogical Kindness. Go to raogk.org Click on Oregon Click on E thru K Scroll down to Harney Co. and choose Lois.
Also the Harney County Historical Museum, cityprofile.com/oregon/harney-county-historical-museum.html has a wide collection of items and information. They are located at 18 West D Street, Burns, Harney Co., OR, 541-573-5618.
The Claire McGill Luce Western History Room in the Harney County Library, harneycountylibrary.org/western-history-room might be another source. They may have a book or two on this mine which you can borrow via inter-library loan. Successful Searching!