Description
Amax Gold Inc.
Commodities
PrimaryGold, Silver
TertiaryClay, Arsenic, Mercury, Sulfur
Commodity typeB
Deposit
Deposit typebedded; hydrothermal breccia; hot springs; other; epithermal
Model104: Hot-spring Au-Ag
Deposit sizeS
Orebody formIRREGULAR
Ore controlThe range front fault system at the NW side of the Lake Range and dilation of faults associated with a gradual collapse centered about 800 meters west of Wind Mountain were responsible for localizing the gold-bearing hydrothermal fluids.
Materials
Ore mineralsElectrum, Cinnabar, Montmorillonite, Illite, Kaolinite, Clay, Alunite, Sulfur, Opal, Chalcedony, Travertine, Calcite, Pyrite, Hematite, Goethite, Jarosite, Mandarinoite
GangueSilica
Geology
Host rockSedimentary Breccia,Conglomerate,Siltstone,Sandstone,Shale,Sedimentary Rock,Basalt · Truckee Formation
Associated rockDacite,Basalt,Tuff,Volcanic Breccia (Agglomerate),Sedimentary Rock · Pyramid Sequence
StructureThere is a major north-striking fault zone dipping steeply west on the western margin of the Lake Range which has hosted extensive hydrothermal alteration and the Wind Mountain Gold Deposit. Two large faults striking N25E bound Breeze Canyon, a small graben, 400 m NW of Wind Mountain. A conjugate system of N30E and N30W- striking high angle, south dipping normal faults cut the entire property. These faults intersect and have broken the mountain into several fault blocks which have been rotated progressively westward from north to south.
AlterationAlteration at Wind Mountain consists of iron-oxide and jarosite staining, argillization, silicification, and acid leaching. Iron-oxide and jarosite staining is the most visually striking characteristic of the Wind Mountain deposit. Strongly argillized rocks occur in an area exceeding 6.5 square km. The clay minerals of 15 samples of intensely argillized rock average 60% montmorillonite, 30% illite, 10% kaolinite, strongly silicified rocks (>70% silica) comprise a zone 100 meters wide and 1700 meters long at the central core and west side of Wind Mountain. About 10% of this silica is light blue colored opaline rock. At least 80% of the silicified rocks consist of dense, hard, crystalline alpha-quartz. Silicified rocks are best developed along high-angle faults (e.g. Wind Mountain fault). Stratiform silicified zones extend over 300 meters from the Wind Mountain fault and generally thin away from the structure. Native sulfur is common in acid leached zones. Three such acid leached zones are recognized, one of which overlies the west side of the Wind Mountain orebody.
Economic & production
Development statusProducer
Production years1989 - 1994
First production1989
Last production1994
Discovery year1988
Identification
Deposit ID10310384
MRDS IDRE00016
Alternate namesNorth Wind, Breeze, Sed Claims
RegionNA
Data scoreB
Coordinates40.4271, -119.39157
References
Garside, L.J., 1983, NBMG Field Examination and Sample Analysis.Amax Gold, Inc., 1988, Environmental Assessment, The Wind Mountain Project.The Mining Record, September 7, 1988, "Amax Gold Proceeding With Wind Mountain Project."Pay Dirt, July 1988, "Amax Gold Sets New Nevada Mine."Wood, J.D., 1991, Geology Of The Wind Mountain Gold Deposit, Washoe County, Nevada, in Raines, G.L., et al., eds., Geology and Ore Deposits of the Great Basin: The Geological Society of Nevada, Reno, p. 1051-1061.NBMG, 1991, The Nevada Minerals Industry - 1990: NBMG Special Publication MI-1990.Mining Journal, Montagu Mining Finance, 8/10/91, Mining Data Base.NBMG, 1994, MI-1993Amax Gold Inc. Annual Report, 1989California Mining Journal, Oct. 1989Nevada Dept. of Minerals, 1994Long, 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.Kinross Gold website.