Abstract The Spring Valley Mining and Irrigation Company was founded in 1875 as a result of the consolidation of earlier companies and mining claims. Hydraulic mining was carried on by the company until 1887. A. W. Mellon of Pittsburgh bought the company in 1900 and changed the name to Cherokee Mining Company. Neither Mellor nor later owners were able to separate the mines successfully. Included in the collection are deeds, mining claims and patents (1857-1891) correspondence (1884-1886,...