- A. Hoen & Co (6)
- Baldwin, Mark (1)
- Banks, Eric H (1)
- Barlow, Alfred E. (Alfred Ernest), 1861-1914 (1)
- Barlow, S (1)
- Bayfield, R. N (1)
- Bayley, William Shirley, 1861-1943 (2)
- Bebb, E. C (2)
- Boatright, W. C (1)
- California State Mining Bureau (1)
- Campbell, Marius R. (Marius Robinson), 1858-1940 (1)
- Chamberlain, T. C (1)
- Chamberlin, Thomas C. (Thomas Chrowder), 1843-1928 (2)
- Chishitsu Cho?sajo (Japan) (1)
- Clements, J. Morgan (Julius Morgan), 1869- (1)
- Cleveland-Cliffs Iron Company (1)
- Collett, John, 1828-1899 (1)
- Colorado Geological Survey (1)
- Cox, E. T. (Edward Travers), 1821-1907 (1)
- Dalson, A. A (1)