Mine detail: Little Rocky Creek Ni-Cu

Previously called 'BenbowRocky GroupChrome Lake'

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Location

Lat / long: 45.35714, -109.80551

Resource(M)

Primary: Nickel, Copper
Secondary: Cobalt
Tertiary: PGE, Silver, Gold
Ore: Chalcopyrite, Pentlandite, Pyrrhotite
Gangue: Magnetite, Plagioclase
Orebody form: MASSIVE AND DISSEMINATED
Discovery year: 1883

Production

Operation type: Unknown
Production size: None
Development status: Occurrence

Geology

Host type:Quartz Monzonite,Peridotite,Hornfels
Structure:The Stillwater Complex Is Exposed Along The Northern Margin Of The Beartooth Uplift, One Of Several Laramide Basement-Cored Ranges That Make Up The Rocky Mountain Foreland Of South-Central Montana (Foose And Others, 1961: Kulik And Schmidt, 1988), Local Faults Of Small Displacement
Tectonic:Tectonic Setting At Time Of Emplacement Of The Stillwater Complex Is Unknown. The Complex Was Emplaced Shortly After A Major Regional, Subduction-Related Magmatic Event That Culminated In Emplacement Of The 2.73-2.79 Ga Granitoid Suite In The Batholith Exposed In The Beartooth Uplift (Wooden And Others, 1991). However, There Is No Evidence That The Magmatism That Formed The Stillwater Complex Is Related To Convergent Margin Tectonics And Magmatism
Alteration processes:None Related To Ore-Forming Process

References

MRDSM060097
DEP10042344
Reference{Deposit:: ROBY, R.N., 1949, INVESTIGATION OF COPPER-NICKEL DEPOSITS OF THE STILLWATER COMPLEX, STILLWATER AND SWEETGRASS COUNTIES, MONTANA: U.S. BUREAU OF MINES REPORT OF INVESTIGATIONS 4431, P. 10.}{Deposit:: HOWLAND, A.L., PEOPLES, J.W., AND SAMPSON, EDWARD, 1936, THE STILLWATER IGNEOUS COMPLEX AND ASSOCIATED OCCURRENCES OF NICKEL AND PLATINUM GROUP METALS: MONTANA BUREAU OF MINES AND GEOLOGY MISCELLANEOUS CONTRIBUTION 7, P. 11.}{Deposit:: PAGE, N.J, RILEY, L.B., AND HAFFTY, JOSEPH, 1969, PLATINUM, PALLADIUM, AND RHODIUM ANALYSES OF ULTRAMAFIC AND MAFIC ROCKS FROM THE STILLWATER COMPLEX, MONTANA: U.S. GEOLOGICAL SURVEY CIRCULAR 624, P. 6.}{Deposit:: PAGE, N.J, RILEY, L.B., AND HAFFTY, JOSEPH, 1972, VERTICAL AND LATERAL VARIATION OF PLATINUM, PALLADIUM, AND RHODIUM IN THE STILLWATER COMPLEX, MONTANA: ECONOMIC GEOLOGY, V. 67, P. 1356-1357.}{Deposit:: ZIENTEK, M.L., 1993, MINERAL RESOURCE APPRAISAL FOR LOCATABLE MINERALS: THE STILLWATER COMPLEX, IN HAMMARSTROM, J.M., ZIENTEK, M.L., AND ELLIOTT, J.E., EDS., MINERAL RESOURCE ASSESSMENT OF THE ABSAROKA-BEARTOOTH STUDY AREA, CUSTER AND GALLATIN NATIONAL FORESTS, MONTANA: U.S. GEOLOGICAL SURVEY OPEN-FILE REPORT 93-207, P. F1-F83.}{Deposit:: PAGE, N.J, 1979, STILLWATER COMPLEX, MONTANA - STRUCTURE, MINERALOGY, AND PETROLOGY OF THE BASAL ZONE WITH EMPHASIS ON THE OCCURRENCE OF SULFIDES: U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1038, 69 P.}{Deposit:: PREMO, W.R., HELZ, R.T., ZIENTEK, M.L., AND LANGSTON, R.B., 1990, U-PB AND SM-ND AGES FOR THE STILLWATER COMPLEX AND ITS ASSOCIATED SILLS AND DIKES, BEARTOOTH MOUNTAINS, MONTANA: IDENTIFICATION OF A PARENT MAGMA?: GEOLOGY, V. 18, P. 1065-1068.}{Deposit:: ZIENTEK, M.L., AND RIPLEY, E.M., 1990, SULFUR ISOTOPIC STUDIES OF THE STILLWATER COMPLEX AND ASSOCIATED ROCKS, MONTANA: ECONOMIC GEOLOGY, V. 85, P. 376-391.}
ReporterDohrenwend, John C., Peterson, Jocelyn A.