Rock Creek

Site Name

Primary: Rock Creek
Secondary: Chicago Peak Prospect
Secondary: Chicago Peak
Secondary: Rock Creek Project

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Commodity

Primary: Copper
Secondary: Silver

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Location

State: Montana
County: Sanders
District: Noxon

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Land Status

Land ownership: National Forest
Note: the land ownership field only identifies whether the area the mine is in is generally on public lands like Forest Service or BLM land, or if it is in an area that is generally private property. It does not definitively identify property status, nor does it indicate claim status or whether an area is open to prospecting. Always respect private property.

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Holdings

Type: Located Claim

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Workings

Type: Underground

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Ownership

Owner Name: Kennecott (Bear Creek Mining Co.)
Percent: 100.0
Info Year: 1984

Owner Name: Asarco (American Smelting And Refining Co.)
Percent: 100.0
Home Office: New York
Info Year: 1984
Years: 1973 -

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Production

Not available

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Deposit

Record Type: Site
Operation Category: Plant
Deposit Type: Sediment-hosted Cu, Revett
Plant Type: Beneficiation (Mill)
Operation Type: Underground
Mining Method: Open Stope - Room and Pillar
Milling Method: Flotation
Discovery Year: 1963
Years of Production:
Organization:
Significant: Y

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Physiography

General Physiographic Area: Rocky Mountain System
Physiographic Province: Northern Rocky Mountains

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Mineral Deposit Model

Model Name: Sediment-hosted Cu, Revett

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Orebody

Not available

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Structure

Type: R
Structure: NORTH TO NORTHWEST-STRIKING MIDDLE PROTEROZOIC FAULTING

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Alterations

Not available

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Rocks

Not available

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Analytical Data

Not available

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Materials

Ore: Bornite
Ore: Chalcocite
Ore: Chalcopyrite
Ore: Silver
Ore: Tetrahedrite
Ore: Galena
Ore: Sphalerite
Ore: Pyrite
Ore: Covellite

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Comments

Comment (Geology): DEPOSITS ARE ASSOCIATED WITH NORTH-NORTHEAST TO NORTHWEST-TRENDING FAULTS (LANGE AND SHERRY, 1983). NORTHWEST-PLUNGING SYNCLINE THAT IS FAULT BOUNDED ON THE SOUTHWEST SIDE BY THE ROCK LAKE FAULT, AND ON THE NORTHEASTBY WHAT APPEARS TO BE THE SOUTHERN EXTENSION OF THE SNOWSHOE FAULT (BURNSIDE AND THOMPSON, 1985).

Comment (Location): Lat/long changed 9/9/2008 because to agree with duplicate record 10048813. Original coordinates were: lat/long NAD27 48-3-7N 115-41-6W (48.0519 -115.685); UTM N5322691 E597996 Z11N; PLSS line# 1: Meridian- Montana Principal, TWNSHP 027 N, RNG 032 W, Sect 26, Sect_fract SWSWSE. From the location description given in comment #2 - LOCATED BENEATH ST. PAUL PEAK AND CHICAGO PEAK, the midpoint of the line connecting the peaks gives 48.0735 -115.686, some 2.6 km N of the original location. The Point of Reference is said to be the ore body, so this conflicts with the original location. Since it is almost due north, it may be a typographical error in the latitude. Or it may relate to some idea to run an adit from non-Wilderness land into the orebody. Boleneus et all, 2005 shows an even more northerly location - NAD27 48.0795 -115.6767. The Boleneus coordinates were used for both records. The old altitude of 1710 m was replaced with that of the new location near St. Paul Peak at 2316 m.

Comment (Deposit): SULFIDE FORMATION OCCURRED AFTER SEDIMENTATION BUT BEFORE LITHIFICATION AND THAT THE DEPOSITS ARE GENETICALLY RELATED TO SYNDEPOSITIONAL BASEMENT-CONTROLLED FAULTS (LANGE AND SHERRY, 1983). THE COPPER-BEARING SULFIDES LOCALLY REPLACE PYRITE, MAGNETITE, SILICATES, AND CARBONATES. (LANGE AND SHERRY, 1983).

Comment (Geology): THE LINEAR DISTRIBUTION OF DEPOSITS WITHIN THE REVETT FORMATION MOST STRONGLY SUPPORTS FAULT-CONTROLLED MINERALIZATION (LANGE AND SHERRY, 1983) THEORY OF FORMATION: SANDSTONE-TYPE DEPOSITS MAY HAVE FORMED AS A RESULT OF THE MIGRATION OF COPPER-SILVER-BEARING SOLUTIONS, POSSIBLY RELEASED DURING SEDIMENT COMPACTION AND DEWATERING, UP SYNDEPOSITIONAL NORTH- TO NORTHWEST-TRENDING BASEMENT-CONTROLLED FAULTS AND INTO PERMEABLE HORIZONS CONTAINING PYRITE AND/OR H2S. (LANGE AND SHERRY, 1983)

Comment (Reserve-Resource): OVERALL ESTIMATED RESOURCE TONNAGE AND GRADE FOR ASARCO?S ROCK CREEK CLAIMS AND U.S. BORAX?S ROCK PEAK AND HEREFORD CLAIMS EXCEEDS 400 MILLION TONS OF 1.56 OZ/TON SILVER AND 0.69 PERCENT COPPER. (FROM MCCULLOCH AND SPEAR, 1983?) PROJECTED ORE FROM 75.0 MILLION TONS ORE: 1.04 BILLION POUNDS COPPER AND 127.9 MILLION OUNCES SILVER. ANOTHER ESTIMATE FROM DOYLE FREDRICK, THE US DEPARTMENT OF THE INTERIOR IN MBMG FILES (1981): EXPLORATION DRILLING, NORTH OF ROCK CREEK, ALONG THE SOUTHWESTERN BOUNDARY OF THE WILDERNESS, IDENTIFIED 4 MILLION TONS OF INDICATED RESERVES AVERAGING 0.86 PERCENT COPPER AND 1.8 OUNCES OF SILVER PER TON; INDICATED RESOURCES ARE ABOUT 20 MILLION TONS AVERAGING 0.29 PERCENT COPPER AND 0.4 OUNCES OF SILVER PER TON. GEOCHEMICAL SURVEYS AND ANALYSES OF ROCK, SOIL, AND STREAM SEDIMENTS INDICATE THAT SOME OF THE MINERALIZED ZONES EXTEND INTO THE WILDERNESS AND CONTAIN ABOUT 70 MILLION TONS OF INFERRED RESOURCES.

Comment (Deposit): (FROM THE SANDERS COUNTY LEDGER, THURSDAY, JUNE 21, 1984) "THE ROCK CREEK OREBODY IS A SILVER-COPPER STRATABOUND DEPOSIT LOCATED BENEATH ST. PAUL PEAK AND CHICAGO PEAK BETWEEN THE 5,000 FOOT AND 5,600-FOOT ELEVATIONS. THE ORE ZONE IS A FLAT LYING DEPOSIT APPROXIMATELY 12,000 FEET LONG, 6,000 FEET WIDE, AND AVERAGES ABOUT 27 FEET THICK. MINERALIZATION IS SIMILAR IN GRADE AND OCCURRENCE TO THE TROY OREBODY ALTHOUGH IT OCCURS AT A LOWER STRATIGRAPHIC HORIZON. REGIONALLY THE STRATABOUND MINERALIZATION OCCURS IN THE REVETT QUARTZITE OF THE BELT SUPERGROUP. THIS NORTH-TRENDING BELT IS ABOUT 120 MILES LONG, 40 MILES WIDE, AND EXTENDS FROM COEUR D?ALENE DISTRICT IN IDAHO INTO CANADA." "THE ASARCO ROCK CREEK PROJECT ENCOMPASSES 1,284 ACRES OF PUBLIC LAND AND 688 ACRES OF LAND THAT ASARCO HAS BOUGHT"

Comment (Geology): THIS IS A STRATABOUND COPPER DEPOSIT STRIKE AND DIP WERE TAKEN FROM CROSS SECTION SKETCHES AND MAY BE INACCURATE MINERALIZED UNIT IS A NORTH PUNGING ANTICLINE

Comment (Location): IN SECTION 26, AND ALSO SECTIONS 33 & 34. INSUFFICIENT DATA AS OF 1993 TO DETERMINE ROCK CREEKS STATUS.

Comment (Reserve-Resource): RESERVES AS OF 03/89. M2C1=MINABLE RESERVES PLANNED FOR EXTRACTION. M1C1=TOTAL DEMONSTRATED RESOURCES

Comment (Workings): PROJECT PROPOSED FOR DEVELOPMENT BY ASARCO MAY 21, 1984. ENVIRONMENTAL IMPACT STUDY TO BEGIN SOON. BASE LINE ENVIRONMENTAL WORK HAS STARTED. ENVIRONMENTAL CONSTRAINTS ON THE PROJECT WOULD BE STRINGENT BECAUSE THE DEPOSIT LIES WITHIN A WILDERNESS. AT ISSUE WOULD BE COMPLINANCE WITH THE 1964 WILDERNESS ACT, THE ENDANGERED SPECIES ACT FOR GRIZZLY BEARS AND CLASS 1 AIR QUALITY DESIGNATED FOR WILDERNESS AREAS. THERE IS MAJOR CONCERN ABOUT TAILINGS CONTAINMENT AT THE PROPOSED SITE NEAR THE CLARK FORK RIVER. POSITIVE ECONOMIC IMPACT OF THE MINE WOULD BE SIGNIFICANT. ASARCO PROPOSES THAT ALL SURFACE OPERATIONS WOULD BE LOCATED OUTSIDE THE WILDERNESS.

Comment (Exploration): 1960?S - BEAR CREEK MINES (A KENNECOTT INC. SUBSIDIARY) STAKED ROCK CREEK CLAIMS. 1966 TO 1973 BEAR CREEK DRILLED 10 DIAMOND DRILL HOLES ADJACENT TO THE WILDERNESS AREA. 1973 - ASARCO ACQUIRES THE RIGHTS TO THE TROY PROJECT AND THE ROCK CREEK PROJECT AND STARTED EXPLORATION. 1979 TO 1983 - 121 DIAMOND DRILL HOLES COMPLETED ON CLAIMS. DECEMBER 31, 1983 - DEADLINE FOR PROVING VALIDITY OF UNPATENTED MINING CLAIMS PER 1964 WILDERNESS ACT. 1984 - EXPLORATION PROGRAM COMPLETED. 1989 - PATENTS FOR MINING CLAIMS GRANTED. 1987 - PERMITTING ACTIVITIES STARTED. 2000 - STERLING MINING COMPANY ACQUIRES 100% OWNERSHIP OF TROY AND ROCK CREEK PROPERTIES FROM KENNECOTT MINERALS COMPANY

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References

Reference (Deposit): WESTERN MINE ENGINEERING, MINING COST SERVICE, 1984.

Reference (Deposit): RM PAYDIRT, WILDERNESS MINES. FEB., 1988. P.12A.

Reference (Deposit): BALLA, J. C. ASARCO MANAGER, NORTHWESTERN EXPLORATION DIVISION. PERSONAL COMMUNICATION, 1984. AVERY, D.W. MONTANA DIRECTORY.

Reference (Deposit): HAYES, T. THE RELATION BETWEEN STRATABOUND COPPER-SILVER ORE AND REVETT FORMATION SEDIMENTARY FACIES AT SPAR LAKE, MONTANA, IN MT BUREAU OF MINES AND GEOL. SPEC. PUBL. 90, 1984, PP. 65-67.

Reference (Deposit): JAYNE, D. I., AND STEBBINS, S. A. THE TROY MINE. UNPUBL.MAS REP., WESTERN FIELD OPERATIONS CENTER, SPOKANE, WA, AUGUST 1984.

Reference (Deposit): PAY DIRT MAGAZINE. ASARCO, U.S. BORAX LOOKING STRONG IN CABINET WILDERNESS WORK. INTERMOUNTAIN ED., JAN. 1984 P. 28A.

Reference (Deposit): SANDERS COUNTY LEDGER. ROCK CREEK PROJECT. JUNE 21, 1984, P. 6,7.

Reference (Deposit): U.S. GEOLOGICAL SURVEY. UNPUBL. DATA, 1984.

Reference (Deposit): WELLS, J. D., D. A. LINDSEY, D. M. KLEINKOPF, BANISTER, D. P R. D. WELDIN, ZILKA, N. T., AND SCHMAUCH, S. W. MINERAL RESOURCES OF THE CABINET MOUNTAINS WILDERNESS, LINCOLN AND SANDERS COUNTIES, MONTANA. U.S. GEOL. SURV. OFR 78-327, 1978, 99 PP.

Reference (Reserve-Resource): MONT. BUREAU OF MINES AND GEOL. BULLETIN 129, 1991,

Reference (Reserve-Resource): WALLACE MINER. WALLACE, IDAHO. ROCK CREEK PROJECT. FEB.,4, 1988, PP. 10A,11A.

Reference (Deposit): AMERICAN SMELTING AND REFING COMPANY (ASARCO). ROCK CREEK PROJECT - PLAN OF OPERATION. SUBMITTED TO THE U.S. FOREST SERVICE, MAY 21, 1984, 42 PP.

Reference (Deposit): Boleneus, D.E., Appelgate, L.M., Stewart, J.H., and Zientek, M.L., 2005, Stratabound Copper-Silver Deposits of the Mesoproterozoic Revett Formation, Montana and Idaho; USGS Scientific Investigations Report 2005?5231, cuag_deposit.txt.

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Principal Gold Districts of Montana

In Montana, 54 mining districts have each have produced more than 10,000 ounces of gold. The largest producers are Butte, Helena, Marysville, and Virginia City, each having produced more than one million ounces. Twenty seven other districts are each credited with between 100,000 and one million ounces of gold production. Read more: Principal Gold Districts of Montana.