AKA: Union Shaft
It appears to be a mine that was developed towards the end of the Comstock boom. According to USGS, the Union was discovered prior to 1879. The first year of real production was in 1879. This is very consistent with my research on Comstock mining deaths. The first death that I found at this mine occurred in 1879 (see below). Silver and gold were primary commodities at this mine. USGS Report Quote: "The mine produced considerable ore from the main Comstock vein at the 2100-ft level. At the 2500-ft level, segments of the east vein were discovered; There, segments, cut by faults, contained minable ore bodies." The Roar and the Silence discusses the flooding that was occurring in the mines in this area of the Comstock in 1879. He stated that the pump that was installed at the Union had a flywheel that was 40 feet in diameter and weighed 110 tons. The cylinder that sucked up the water was over 5 feet in diameter. It was capable of sucking up all the water in a small room in one cycle of the action. The book also spoke about how the freighters who hauled this type of equipment into these mines eventually attained the status of "local legend". These pumps were so noisy, that when paired with the rumble of the mills, created a constant noise heard throughout the Comstock.
Union Mine- Mining Deaths- (1863 through 1883):
John Retallack- October 28; Hugh B. Malloy & T.C. McCarthy (McCarty)- December 2.
David Schollar (or John Schollar)- April 22; John Abbott & Duncan A. Bethune- July 2.
W.H. Abbott- January 25; Murdock McLannan (or Murdoch McLellan)- March 11; John Lloyd- December 6.
John Beargo, John Black & James Brown- June 12.
Marshal S. Powers- January 23.
Sources: The Roar and the Silence- A History of Virginia City and the Comstock Lode (By: Ronald M. James); USGS MRDS Reports- 10043943 Union Mine; 10150458 Union Shaft; (Mining Deaths) Gold Hill Daily News (Newspaper); Carson Morning Appeal/ Carson Daily Appeal (Newspaper); Elko Independent (Newspaper); Virginia Evening Chronicle (Newspaper); Daily Silver State/ The Silver State (Newspaper); Lyon County Times (Newspaper); Eureka Daily Sentinel (Newspaper); Pioche Weekly Record (Newspaper);