Commodities
PrimaryGold, Silver
SecondaryCopper, Lead, Zinc
TertiaryAluminum, Iron, Manganese, Molybdenum
Commodity typeM
Deposit
Deposit typevein/shear zone; epithermal
Model150: Epithermal vein, Comstock
Deposit sizeY
Orebody formshoots, stringers, irregular replacement bodies
Ore controlProximal to contact between volcanics or limestone and intrusive bodies; shear zone; NW-trending fault; ore mainly on hanging wall of fault zones up to 50 feet wide. NW-trending fault; ore mainly on hanging wall of fault zones up to 50 feet wide. Clay seams and altered areas of andesite tended to concentrate secondary ore.
Materials
Ore mineralsGold, Cerargyrite, Chrysocolla, Malachite, Chalcopyrite, Galena, Jarosite, Argentite, Alunite, Silver, Electrum, Cerussite, Wulfenite
GangueQuartz, Sericite, Kaolin, Alunite, Adularia
Geology
Host rockFelsic Volcanic Rock,Rhyolite,Tuff,Ash-Flow Tuff,Andesite,Volcanic Rock (Aphanitic),Limestone · Luning Formation
Associated rockDiorite,Granodiorite,Quartz Monzonite
StructureThe area is structurally complex, with dominantly NW- to WNW- trending high angle faults, down to the north. In the western part of the district, faults appear antithetic, having their upthrown sides to the south, A NW-trending fault offsets ash-flow tuff sequence.
AlterationAdvanced argillic type of alteration is prevalent with veins of alunite and quartz. Limonite, and kaolinite replacing wall rock minerals predominates in the vicinity of the Golden Pen and Lone Star claims. At the Nevada Rand area, alteration is sericitic or phyllic in nature. Intermediate lavas from both areas show propylitic alteration. Bleached andesite and development of jarosite due to oxidation of numerous small crystals of disseminated pyrite. Alunitization of host rock is present.
Economic & production
Development statusPast Producer
First production1910
Discovery year1907
Identification
Deposit ID10310399
MRDS IDM035744
Alternate namesBovard - Rand Property, Blue Sphinx Mine, Bovard Mine, Golden Pen Mine
RegionNA
Data scoreB
Coordinates38.79992, -118.40096
References
Ross, D. C., 1961 , Geology and Mineral Deposits of Mineral County, Nevada: NBMG Bull. 58 , P. 80 .Schrader, F. C., 1914 , Alunite at Bovard, Nev.: USGS Bull. 540 , p. 351 - 356 .Thoenen, J. R., 1941 , Alunite Resources of the United States: USBM R. I. 3561 , p. 19 - 20 .Vanderberg, W. O., 1937 , Reconnaissance of Mining Districts in Mineral County Nev.: USBM I. C. 6941 , p. 57 - 58 .Black, J.W., 1920, unpublished reportLong, K.R., DeYoung, J.H., Jr., and Ludington, S.D., 1998, Database of significant deposits of gold, silver, copper, lead, and zinc in the United States; Part A, Database description and analysis; part B, Digital database: U.S. Geological Survey Open-File Report 98-206, 33 p., one 3.5 inch diskette.http://www.goldsummitcorp.com/bluesphinx1.htmpress releases