Knob Hill Mine

Producer in Ferry county in Washington, United States with commodities Gold, Silver, Selenium, Tellurium, Arsenic, Copper, Antimony
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Public Land Survey System information
  6. Commodities
  7. Materials information
  8. Alteration
  9. Mineral occurrence model information
  10. Host and associated rocks
  11. Nearby scientific data
  12. Geologic structures
  13. Ore body information
  14. Controls for ore emplacement
  15. Economic information about the deposit and operations
  16. Mining district
  17. Ownership information
  18. Production statistics
  19. Reserves and resources
  20. Links to other databases
  21. Bibliographic references
  22. General comments
  23. Reporter information

Geologic information

Identification information

Deposit ID 10041109
MRDS ID M056035
Record type Site
Current site name Knob Hill Mine
Alternate or previous names Veins: Knob Hill, Stewart, Golden Promise, South Cross, Alpine, Bailey
Related records 10277450, 10301483

Geographic coordinates

Geographic coordinates: -118.75947, 48.67262 (WGS84)
Elevation 951
Relative position 2.05 MI NW OF REPUBLIC, WA.

Site location context

Political divisions (FIPS codes)

Ferry(county)

Washington(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Storm King Mountain(quadrangle 1:24,000 scale)

Republic(quadrangle 1:100,000 scale)

Okanogan(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Sanpoil(hydrologic unit)

Upper Columbia(hydrologic accounting unit)

Upper Columbia(hydrologic subregion)

Pacific Northwest(hydrologic region)

Geographic areas

Country State County
United States Washington Ferry

Public Land Survey System information

Meridian Township Range Section Fraction State
037N 032E 27 Washington

Commodities

Commodity Importance
Gold Primary
Silver Primary
Selenium Tertiary
Tellurium Critical Tertiary
Arsenic Critical Tertiary
Copper Tertiary
Antimony Critical Tertiary

Comments on the commodity information

  • APROX. 40% OF AU OCCURS AS FREE GRAINS OF ELECTRUM, THE REMAINDER PROBABLY AS SELENIDES AND TELLURIDES. THE PRINCIPAL ORE MINERAL OF AG IS NAUMANNITE. THE AU:AG RATIO RANGES 1:1.5 TO 1:9, AVERAGES 1:5, AND USUALLY DECREASES WITH DEPTH BY INCREASE IN AG GRADE.

Materials information

Materials Type of material
Electrum Ore
Naumannite Ore
Tetrahedrite Ore
Barite Gangue
Calcite Gangue
Chalcedony Gangue
Chalcopyrite Gangue
Fluorite Gangue
Gypsum Gangue
Marcasite Gangue
Opal Gangue
Pyrite Gangue
Quartz Gangue
Realgar Gangue
Sericite Gangue
Stibnite Gangue

Alteration

  • (Local) Propylitization And Silicification. See Geology Comments.

Mineral occurrence model information

Model code 150
USGS model code 25c
Deposit model name Epithermal vein, Comstock
Mark3 model number 16

Host and associated rocks

  • Host or associated Host
    Rock type Volcanic Rock (Aphanitic) > Felsic Volcanic Rock > Quartz Latite
    Rock unit name Sanpoil Volcanics;Knob Hill Stock
    Rock description Sanpoil Volcanics;Knob Hill Stock

Nearby scientific data

(1) -118.75947, 48.67262

Economic information

Geologic structures

Type of structure Regional
Structure description The Republic Graben Trends Northeasterly And Is Bounded On The West By The Bacon Creek Fault And On The East By The Sherman Creek Fault.
Type of structure Local
Structure description Eureka Fault System.

Ore body information

  • Width 4.57M

Controls for ore emplacement

  • Gold Deposition Is Believed To Be Genetically Connected With The Intrusion Of The Quartz Latite Porphyry Stock. Dextral Strike Slip Movement On The Eureka Fault System Is Believed To Have Created The Shears And Dilational Zones Which Were Subsequently Mineralized. Flexures Or "Rolls" In The Veins From Steeper To Flatter Dips Are Very Important Controls Of High Grade Ore. Ore Is Hosted Mainly By Sanpoil Volcanics, With Minor Amounts Of Ore In The Knob Hill Stock.

Comments on the geologic information

  • ALTERATION COMMENTS: PROPYLITIZATION AND SILICIFICATION. AMPHIBOLES ALTERED TO CHLORITE-CARBONATE, FELDSPARS ALTERED TO SERICITE AND CARBONATE. SILICIFICATION IS PREDOMINANT PROXIMAL TO UPPER LEVEL VEINS. GEOLOGY COMMENTS: GOLDEN PROMISE VEINS OCCUR BETWEEN TWO RIGHT LATERAL STRIKE SLIP FAULTS, THE HERMES SHEAR AND THE CROSBY SHEAR, KNOWN IN MINE USAGE AS THE "SHEAR COUPLET". BLACK CHALCEDONY ASSOCIATED WITH THE THE GOLDEN PROMISE NO. 1 VEIN IS UNIQUE IN THE DISTRICT. IN THE GOLDEN PROMISE VEINS, VEIN TEXTURES RANGE FROM BANDED TO COLLIFORM TO BOTRYOIDAL TO "BAROQUE" (MINE TERM FOR A FLOWERY, ORNATE TEXTURE ASSOCIATED WITH THE HIGHEST GRADES). THE NEARBY STEWART, MOUNTAIN LION, AND MUD LAKE PITS ARE HOSTED IN PART BY VOLCANICLASIC SEDIMENTS (LOWERMOST KLONDIKE MOUNTAIN FORMATION?) AND ARE ASSOCIATED WITH ARGILLIZATION AND HYDROTHERMAL BRECCIATION.

Economic information about the deposit and operations

Development status Producer
Commodity type Metallic
Deposit size Medium
Significant No
Discovery year 1904
Year of first production 1904
Production years 1904; 1910-1926; 1930-1935; 1937-PRESENT (11/92)

Mining district

District name Republic District

Ownership information

  • Type Owner-Operator
    Owner Hecla Mining Co.

Production statistics

  • Year 1987
    Material AU
    Accuracy Accurate
    Description Ap_Grade: ^4.70 Opt Au Recovered Grade
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Gold Gold 11g/mt
  • Year 1987
    Material ORE - AU,AG
    Accuracy Accurate
    Description Ap_Grade: ^0.97 Opt Au Recovered Grade
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Gold Gold 27g/mt
  • Year 1988
    Material AG
    Accuracy Accurate
    Description Ap_Grade: ^0.90 Opt Au Recovered Grade
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Gold Gold 25g/mt
  • Year 1989
    Material ORE - AU,AG
    Accuracy Accurate
    Description Ap_Grade: ^3.60 Opt Ag Recovered Grade
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Ore Silver Silver 102g/mt

Comments on the production information

  • PRODUCTION FROM THE KNOB HILL NO. 2 SHAFT REACHED 2 MILLION OUNCES AU ON MAY 24, 1989.

Reserves and resources

  • Type In-situ
    Estimate year 1990
    Commodity Subtype Grade units Group Importance Year
    Gold Au 18.353 g/mt Gold Major 1990
    Silver Ag 98.824 g/mt Silver Major 1990

Comments on the reserve resource information

  • 1990 FIGURES REPRESENT PROVEN AND PROBABLE RESERVES AS OF 12/31/90.

Comments on the workings information

  • THE MILL, CONSTRUCTED IN 1937, WAS OPERATING IN 1990 AT A RATE OF 270 TPD WHICH IS THE DAILY HOISTING CAPACITY OF THE NO. 2 SHAFT. THE NO. 2 SHAFT REACHES AN INCLINED DEPTH OF 2000 FT. DOWN THE DIP OF THE VEIN. OVERHAND CUT AND FILL IS THE MINING TECHNIQUE. BY THE END OF 1990, THE DECLINE RAMP BEING DRIVEN TO ACCESS THE GOLDEN PROMISE VEIN HAD REACHED A LENGTH OF 13,000 FT. THE DECLINE RAMP IS 13 FT. HIGH, 15 FT. WIDE, AND EXTENDS DOWNWARD AT A 14% GRADE. MOST OF THE WASTE ROCK FROM CUTTING THE DECLINE HAS BEEN USED BY FERRY COUNTY FOR ROAD FILL. THE NEW DECLINE ALLOWS RUBBER-TIRED TRUCKS TO DRIVE DIRECTLY TO AND FROM THE UNDERGROUND WORKINGS, PROVIDING AN INCREASE IN MINING AND DEVELOPMENT ACTIVITIES.

Comments on development

  • MILL.CAP: 270 TPD ; ECON.COM: IN 1990, CASH COST OF PRODUCTION WAS $130 PER OZ. OF AU AND FULL COST OF PRODUCTION WAS $150 PER OZ OF AU. STUDIES WERE SCHEDULED FOR 1991 ON WHETHER INCREASED RESERVES WOULD JUSTIFY AN INCREASE IN THE MILL'S 270 TPD CAPACITY.

Reference information

Bibliographic references

  • Deposit

    USGS BULL 1216, PG 114

  • Deposit

    HECLA MINING CO., 1991, ANNUAL REPORT FOR 1990.

  • Deposit

    DAYTON, S.H., 1988, HECLA'S REPUBLIC UNIT: SMALL MINE PACKS A BIG EARNINGS PUNCH, ENGINEERING AND MINING JOURNAL, DECEMBER, P. 34-39.

  • Deposit

    LASMANIS, R., WASHINGTON GEOLOGIC NEWSLETTER, VOL. 17, NO. 3, P. 9-11.

  • Deposit

    LINDGREN, W. AND BANCROFT, H., 1914, THE ORE DEPOSITS OF NORTHEASTERN WASHINGTON, USGS BULLETIN 550, P. 133-166.

  • Deposit

    UMPLEBY, J., 1910, GEOLOGY AND ORE DEPOSITS OF REPUBLIC MINING DISTRICT, WASHINGTON GEOLOGICAL SURVEY BULLETIN NO. 1.

  • Deposit

    SALZER, T.A., 1990, EPITHERMAL GOLD-SILVER DEPOSITS, REPUBLIC DISTRICT, FERRY COUNTY, WASHINGTON, ORAL PRESENTATION AT 96TH ANNUAL NORTHWEST MINING ASSOCIATION CONVENTION, SPOKANE, WA, DECEMBER 7.

  • Deposit

    MARTIN, W., 1988, THE GEOCHEMISTRY AND PETROGRAPHY OF SOME VEINS AND WALLROCKS HOSTING GOLD AND SILVER IN THE REPUBLIC DISTRICT, NORTHEASTERN WASHINGTON, UNPUBLISHED M.S. THESIS, EASTERN WASHINGTON UNIVERSITY.

  • Deposit

    FULL, R. P. AND GRANTHAM, R. M., 1968, ORE DEPOSITS OF THE REPUBLIC MINING DISTRICT, FERRY COUNTY, WASHINGTON, IN RIDGE, J. D., ED., ORE DEPOSITS OF THE UNITED STATES 1933-1967 - THE GRATON SALES VOLUME, THE AMERICAN INSTITUTE OF MINING, METALLURGICAL, AND PETROLEUM ENGINEERS, INC., NEW YORK, P. 1481-1494.

  • Production

    1986-1990 ANNUAL PRODUCTION: HECLA MINING CO., 1991, ANNUAL REPORT FOR 1990. DAYTON, S.H., 1988, HECLA'S REPUBLIC UNIT: SMALL MINE PACKS A BIG EARNINGS PUNCH, ENGINEERING AND MINING JOURNAL, DECEMBER, P. 34-39. LASMANIS, R., WASHINGTON GEOLOGIC NEWSLETTER, VOL. 17, NO. 3, P. 9-11.

General comments

Subject category Comment text
Deposit TWO VEIN TYPES ARE RECOGNIZED: 1) SHEAR VEINS - LONG DIMENSION IS ALONG STRIKE, SHORT DIMENSION IS DOWN DIP, NARROWER THAN DILATIONAL VEINS, GENERALLY HOST LOWER GRADE ORE, STRIKE NW, EXAMPLE IS BAILEY VEIN. 2) DILATIONAL VEINS - LONG DIMENSION IS DOWN DIP, SHORT DIMENSION IS ALONG STRIKE, WIDER THAN SHEAR VEINS, GENERALLY HOST HIGHER GRADE ORE.
Deposit THIS RECORD HAS BEEN MERGED WITH SP00082, WHICH HAS BEEN DELETED.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-JUN-1974 Greene, Robert U.S. Geological Survey
Updater 01-NOV-1992 Phinisey, J. D. (Marcus, S.) U.S. Geological Survey

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.

External references