Empire District
The Empire district is in the Empire Mountains (T. 18 S., R. 17 E.), which extend northeastward from the Santa Rita Mountains; the lode deposits of the district are primarily base-metal replacement and contact deposits. In 1935, 2 ounces of placer gold was reportedly recovered, but the location and source of this placer is unknown.
Literature
Wilson, 1951: Describes principal mines in the Empire district.
Old Baldy District (Madera Canyon Placers)
Madera Canyon is on the northwest slope of the Santa Rita Mountains (T. 19 S., R. 14 E.). Reportedly there was considerable placer mining in the lower part of the Madera Canyon alluvial fan in the late 1880's, but I have found no record of any placer gold produced in this district. The only recent activity reported was for 1932-33, when the deposits were sampled.
Literature
Schrader, 1915: Location, extent, depth of gravels; early placermining activity. Wilson, 1961: Virtually quotes Schrader (1915); placer-mining activity during the period 1932-33.
Silver Bell District
No information has been found describing placer deposits in the Silver Bell district, Silver Bell Mountains (Tps. 11 and 12, S., R. 8 E.) about 40 miles northwest of Tucson.
