Lake Serene Mine located in Snohomish County, part of the Index Mining District. Also known as the Index-Independent, Wilbur Index, and Pride of Index mine.
Ore consisted primarily of copper with gold and silver. From 1902 - 1907 the mine was owned by the Index-Independent Mining Company. From 1949 - 1951 the mine was owned by the Lake Serene Mining Company.
Above ground structures consisted of a cabin and 80 ton bunker. The development consisted of three adits, one 470 feet, one 170 feet, and one 261 feet. Assays consisted of high grade ore at $98.98 a ton.
Source: Inventory of Washington Minerals Part II
Huntting M.T. 1956