Commodities
PrimaryGold, Silver
Commodity typeM
Deposit
Deposit typefissure veins, lodes; replacement
Model150: Epithermal vein, Comstock
Deposit sizeY
Orebody formTabular to irregular
Ore controlOre is generally controlled by faults in volcanic rocks, trending N30 to 60 W, dipping 65 NE to vertical; ore is also generally restricted to the bleached zone.
Materials
Ore mineralsPyrite, Stromeyerite, Gold, Tetrahedrite, Proustite, Chalcopyrite, Sphalerite, Adularia, Quartz
GangueCalcite
Geology
Host rockRhyolite,Andesite
Associated rockRhyolite,Tuff,Porphyry,Limestone
StructureVolcanic centers of several ages occur in the region of the deposit.\n\n, NW-trending faults
Tectonic settingmiogeosynclinal, Basin and Range
AlterationA zone of hydrothermally bleached country rock covers a 3 square mile area surrounding the deposit. Host rocks are silicified.
Economic & production
Development statusPast Producer
First production1908
Last production2006
Discovery year1907
Identification
Deposit ID10310524
Alternate namesMidas deposit, Rex-Grande, Midas Joint Venture
RegionNA
Data scoreB
Coordinates41.24379, -116.80095
References
Rott, E H. 1931, Ore deposits of the Gold Circle Mining District, Elko Co., Nev.: Nevada Univ: Bull., V. 25, No. 5, 30 p.Koschmann, A. H. and Bergendahl, M. H., 1968, Principal gold producing districts in the U.S.: USGS Prof. Paper 610, p. 176Emmons, W. H., 1910, Reconnaissancce of Mining Camps in Elko, Lander, Eureka Cos., Nevada: USGS Bull. 408, p. 48Roberts et al., 1971, Gold bearing deposits, Nevada and Idaho: Econ. Geol., Vol. 66, No 1 p. 30LaPointe and others, 1991, NBMG Bull. 106NBMG MI-94 thru MI-98NBMG Map 91, 1st, 2nd, 3rd editionsAmer. Mines (1996), 1995 thru (2000), 1999Patrick Goldstrand, oral communication, 1999Tuscarora Land Status Map, 1979MASMILS 0320070203, 0320070642GSN SP29Long, K.R., DeYoung, J.H., Jr., and Ludington, S.D., 1998, Significant deposits of gold, silver, copper, lead, and zinc in the United States: U.S. Geological Survey Open-File Report 90-206A, 33 p.; 98-206B. one 3.5 inch diskette.