Geology
Host rockChert,Argillite,Siltstone,Quartzite · Valmy Formation
Associated rockDacite,Porphyry,Quartz Monzonite
StructureHilltop Mine Fault, The Hilltop deposit falls within the Battle Mountain-Eureka mineral belt.
Tectonic settingComplex structural history of thrust faulting and normal faulting
AlterationThere have been two main alteration episodes: one pre-ore consisting of pervasive quartz-sericite-pyrite, and one coeval with gold deposition pervasive silicification, bleaching, baritization, and alunitization. Hydrothermal alteration of the Valmy Formation is predominantly bleaching (removal of organic carbon) and recrystallization/silicification resulting from the emplacement of Tertiary igneous intrusions. Tertiary igneous units exhibit typical phyllic alteration with local argillic alteration.\n\n
References
NBMG Mining District File 153, Numerous press clippingsLisle, R.E. and Desrochers, G.J., 1988, Geology of the Hilltop Gold Deposit, Lander County, Nevada in GSN Precious Metals Symposium Technical Volume.Bonham, H.F., 1986, NBMG Map 91Bonham, H.F., 1988, in NBMG MI-1987NBMG, 1994, MI-1993Long, 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.Kelson, C.R., Keith, J.D., Christiansen, E.H., and Meyer, P.E., 2000, Mineral paragenesis and depositional model of the Hilltop gold deposit, Lander County, NV, in Cluer, J.K., Price, J.G., Struhsacker, E.M., Hardyman, R.F., and Morris, C.L., eds., Geology and ore Deposits 2000: The Great Basin and Beyond: Geological Society of Nevada Symposium Proceedings, Reno/Sparks, May 2000, p.1107-1132.http://www.arizonastar.com/337/Hilltop-Slaven_Property.htm