1. Mineral Resources
  2. Online Spatial Data
  3. Mineral Resource Data System (MRDS)

Silver Dyke Mine

Past Producer in Cascade county in Montana, United States with commodities Copper, Lead, Silver, Zinc, Gold
Map
XML
JSON
KML
A
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. Workings at the site
  20. Links to other databases
  21. Bibliographic references
  22. General comments
  23. Reporter information

Geologic information

Identification information

Deposit ID 10071338
MRDS ID W014671
Record type Site
Current site name Silver Dyke Mine

Geographic coordinates

Geographic coordinates: -110.69528, 46.98352 (WGS84)
Elevation 2134
Relative position ABOUT 30 KM NORTHEAST OF NEIHART

Site location context

Political divisions (FIPS codes)

Cascade(county)

Montana(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Neihart(quadrangle 1:24,000 scale)

White Sulphur Springs(quadrangle 1:100,000 scale)

White Sulphur Springs(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Belt(hydrologic unit)

Upper Missouri(hydrologic accounting unit)

Missouri-Marias(hydrologic subregion)

Missouri(hydrologic region)

Federal lands

Helena-Lewis and Clark National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State County
United States Montana Cascade

Public Land Survey System information

Meridian Township Range Section Fraction State
Montana Principal 014N 008E 10 Montana

Comments on the location information

  • UTM COORDINATES OF CENTER OF GLORY HOLE

Commodities

Commodity Importance
Copper Primary
Lead Primary
Silver Primary
Zinc Critical Secondary
Gold Secondary

Comments on the commodity information

  • ORE MINERALS OCCUR IN SMALL VEINLETS AND SMALL CLUSTERS BETWEEN BRECCIA FRAGMENTS AND TO A SLIGHT EXTENT IN FINE-GRAINED DISSEMINATION THROUGH THE ROCK.

Materials information

Materials Type of material
Chalcopyrite Ore
Galena Ore
Malachite Ore
Pyrite Ore
Sphalerite Ore
Tetrahedrite Ore
Cerussite Ore
Azurite Ore
Quartz Gangue
Barite Gangue
Hematite Gangue

Alteration

  • (Local) Host Rock Highly Altered To Kaolin, Sericite And Quartz.

Mineral occurrence model information

Model code 85
USGS model code 22c
Deposit model name Polymetallic veins
Mark3 model number 46

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite
    Rock unit name Snow Creek Porphyry-Pluton & Dikes Of Rhyolite Porphyry & Alaskite;Carpenter Creek Porphyry-Dikes Of Granite Porphyry;Pinto Diorite-Large Phenocrysts Of Feldspar & Hornblende
    Rock description Snow Creek Porphyry-Pluton & Dikes Of Rhyolite Porphyry & Alaskite;Carpenter Creek Porphyry-Dikes Of Granite Porphyry;Pinto Diorite-Large Phenocrysts Of Feldspar & Hornblende
    Stratigraphic age (youngest) Pliocene
    Stratigraphic age (youngest) Pliocene
  • Host or associated Associated
    Rock type Volcanic Rock (Aphanitic) > Felsic Volcanic Rock > Rhyolite
  • Host or associated Host
    Rock type Metamorphic Rock > Gneiss
  • Host or associated Host
    Rock type Volcanic Rock (Aphanitic) > Pyroclastic Rock > Volcanic Breccia (Agglomerate)
    Rock unit name Silver Dyke Breccia-Fragments Of Granite & Rhyolite Porphyry And Gneiss;Gneiss
    Rock description Silver Dyke Breccia-Fragments Of Granite & Rhyolite Porphyry And Gneiss;Gneiss

Nearby scientific data

(1) -110.69528, 46.98352
ListMap

Economic information

Geologic structures

Type of structure Regional
Structure description Zone Of Igneous Intrusions Covering Over 800 Square Km
Type of structure Local
Structure description Domal Uplift Caused By Intrusion Of Snow Creek Porphyry, Northeast-Trending Fractures And Faults

Ore body information

  • General form ELLIPTICAL PIPE
    Length 150M
    Width 300M
    Depth to top 0M

Controls for ore emplacement

  • Breccia Pipe, Junction Of Rhyolite Porphyry And Granite Porphyry Dikes, Whippoorwill And Savage Veins

Comments on the geologic information

  • PRECAMBRIAN ROCKS ARE PRE-BELT. SNOW CREEK PORPHYRY ALSO CALLED NEIHART PORPHYRY AND CARPENTER CREEK PLUTON BUT CARPENTER CREEK PLUTON IS POOR NAME BECAUSE OF CONFUSION WITH CARPENTER CREEK PORPHYRY
  • ?THE ORIGIN OF THE ORE HAS NOT BEEN DEFINITELY DETERMINED. IT IS POSSIBLE THAT BRECCIATION OCCURRED WHEN THE CARPENTER CREEK PORPHYRY WAS INJECTED INTO THE MORE BRITTLE SNOW CREEK PORPHYRY. SOLUTIONS CONTAINING THE ORE MINERALS PENETRATED INTO THE BRECCIA AND WERE DEPOSITED IRREGULARLY. THE NEARBY WHIPOORWILL AND SAVAGE VEINS MAY HAVE BEEN THE FEEDER CHANNELS THROUGH WHICH THE MINERAL-BEARING SOLUTIONS CIRCULATED.? (ROBERTSON, 1951)



    ?MINERALIZATION ... CONTROLLED BY THE BRITTLENESS OF THE COUNTRY ROCK AND TO SOME DEGREE BY THE HYDROTHERMAL ALTERATION WHICH AFFECTED THE INTERSTITAL POROSITY AND PERMEABILITY BETWEEN BRECCIA FRAGMENTS? (CROWLEY, 1970)
  • ?THE BRECCIA PIPE AT THE SILVER DYKE IS IN AN ELBOW OF A QUARTZ LATITE DIKE. THE ELBOW IS THE RESULT OF A CHANGE IN STRIKE FROM EAST-WEST TO SLIGHTLY EAST OF NORTH. A SMALL, NORTHWEST-STRIKING QUARTZ PORPHYRY HAS BEEN EMPLACED AT THE ELBOW. A BRECCIA PIPE WITH A DIAMETER OF ABOUT 500 FEET EMBRACES MOST OF THE QUARTZ PORPHYRY, THE NORTHERN EDGE OF THE QUARTZ LATITE, AND A ROUGHLY CIRCULAR AREA OF GNEISSES NORTH OF THE JUNCTION OF THE TWO PORPHYRIES.? (CROWLEY, 1970)

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic
Deposit size Small
Significant Yes
Discovery year 1875
Year of first production 1921

Mining district

District name Neihart District

Ownership information

  • Type Operator
    Owner Peter Antonioli And Son
  • Type Owner
    Owner Peter S. Antonioli And Son
    Home office 1001 West Gold, Butte, Mt 59701

Production statistics

  • Year 1948
    Period 1921-1948
    Material ore
    Ore mined 1059000mt
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Minor AU Gold Gold 0.05mt
    Major AG Silver Silver 98.82mt
    Major PB Lead Lead 7424291.04mt
    Major CU Copper Copper 3.38mt

Comments on the production information

  • AVERAGE METAL RECOVERY ABOUT 75%. OVER 90% OF PRODUCTION BETWEEN 1923 AND 1929. SPORADIC PRODUCTION BY LESSEES SINCE 1929
  • PRODUCTION FROM 1921 TO 1948 WAS: 1,167,125 TONS OF ORE FROM WHICH 1,736.67 OZ AU, 3,177,068 OZ AG, 7,453,527 LBS CU, 16,367 LBS PB, AND 8,428 LBS ZN WAS RECOVERED (ROBERTSON, 1951)

    AVERAGE GRADE FOR THE MILLION TONS OF ORE MINED IN THE 1920?S WAS 1.5% PB, 0.75% CU, AND 5 OZ AG (CROWLEY, 1971)

Comments on the reserve resource information

  • RESOURCES MAY BE EXPECTED IN TWO AREAS: (1) BENEATH THE OPEN PIT AND (2) IN THE REMAINING BRECCIA. MINE WAS PROBABLY CLOSED MORE BECAUSE OF DECLINING METAL PRICES IN 1929-1930 RATHER THAN BECAUSE OF EXHAUSTION OF MINERALIZED GROUND. ABOUT 2,500,000 ST OF BRECCIA WAS EXTRACTED AND ABOUT 2,000,000 ST REMAINS ABOVE ADIT LEVEL. A LARGE AMOUNT OF LOW-GRADE ROCK PROBABLY LIES BENEATH ADIT LEVEL WHICH COULD BE EXTRACTED FROM AN ADIT DRIVEN FROM SQUAW CREEK, POSSIBLY ALONG THE SAVAGE VEIN. AN ADIT AT 6400 FT. WOULD GIVE ACCESS TO AN ESTIMATED 3,000,000 ST MINERALIZED ROCK, ASSUMING AN ORE BODY SHAPED LIKE A VERTICAL INVERTED CONE WITH THE APEX AT AN ELEVATION OF 6400 FT. ABOUT HALF THIS TOTAL, OR 3,000,000 ST MIGHT BE EXPECTED TO CARRY ABOUT 2 TOZ/ST AG.

Workings at the site

  • Type of workings Surface/Underground
    Length 1000M
    Overall depth 100M
    Overall length 182.88M
    Overall width 150M

Comments on the workings information

  • DEPOSIT DEVELOPED BY A COMBINATION OF OPEN CUTS WITH SURFACE DRILLING AND BLASTING AND SHRINKAGE STOPES FROM BENEATH. ORE WAS DROPPED DOWN CHUTES TO ADIT LEVEL AND TRAMMED TO THE MILL.

    GLORY HOLE AND OPEN CUTS



    6,864? LEVEL HAS OVER 3,000 FT OF DRIFTS AND CROSSCUTS; AN UPPER LEVEL AT 7,040? HAD 2,800 FT OF DRIFTS AND CROSSCUTS (THIS LEVEL OBLITERATED BY OPEN PIT); ALSO SOME INTERMEDIATE DRIFTS. (CROWLEY, 1970)

Comments on development

  • MINOR EXPLORATION AND DEVELOPMENT OVER PAST FEW YEARS INCLUDING DRILLING BY VARIUS COMPANIES
  • 1922-23 - 500-TON CONCENTRATING MILL CONSTRUCTED BY STEARNS AND ROGERS (ROBERTSON, 1951).

    1923 - AMERICAN ZINC, LEAD, AND SMELTING COMPANY ACQUIRES THE PROPERTY.

    1926 - MILL CAPACITY INCREASED TO 950-TON PER DAY.

    1929 - BLOCKED OUT ORE DEPLETED.

    1947 - SILVER DYKE MINING COMPANY DISSOLVED APRIL 8, 1947 (SUBSIDARY OF THE AMERICAN ZINC, LEAD, AND SMELTING COMPANY).

    1951 - PROPERTY OWNED BY H.L. MAURY AND A.G. SHONE OF BUTTE.

    1966 - FREEPORT SULFUR COMPANY CONDUCTED A GEOLOGICAL EXPLORATION PROGRAM.

    1970 - ANACONDA COMPANY DRILL PROJECT AT THE SILVER DYKE.

    1967-1983 - LISTED AS `DEVELOPING? IN MBMG FILES

    1984 - TO PRESENT - INACTIVE

    MINOR EXPLORATION AND DEVELOPMENT OVER PAST FEW YEARS INCLUDING DRILLING BY VARIOUS COMPANIES

Reference information

Bibliographic references

General comments

Subject category Comment text
Deposit GRAVITY DATA INDICATE A PLUTON OF SNOW CREEK PORPHYRY UNDERLIES SILVER DYKE MINE AND EXTENDS AS MUCH AS 5 KM TO THE NORTHEAST WITH A WIDTH OF ABOUT 3 KM. LACK OF STRONG FAULTS PASSING THROUGH BRECCIA AND LARGE AMOUNT OF LOCALIZED HYDROTHERMAL ALTERATION INDICATES THAT THE BRECCIA PIPE IS A DIATREME.
Deposit Discovery Year: LATE 1800'S
Deposit MINERALS OCCURRED AS DISSEMINATIONS IN A BRECCIATED MASS OF QUARTZ PORPHYRY, GRANITE PORPHYRY, AND GNEISS.? (ROBERTSON, 1951).



?ORE WAS A COMPLEX MIXTURE OF BOTH SULFIDE AND OXIDE OR CARBONATE MINERALS DISSEMINATED IN A GANGUE OF HIGHLY ALTERRED QUARTZ PORPHYRY AND GNEISS.? (ROBERTSON, 1951).



RATIO OF LEAD TO SILVER IS 1 PERCENT LEAD TO 3 OR LESS OUNCES SILVER (CROWLEY, 1970)



?QUARTZ, BARITE, AND THE PRIMARY SULFIDES HAVE BEEN DEPOSITED AS BRECCIA FILLINGS SURROUNDING ALTERED FRAGMENTS OF QUARTZ PORPHYRY, QUARTZ LATITE PORPHYRY, AND GNEISSES. THE BREECCIA FILLINGS TAKE THE FORM OF DRUZY CRUSTS BETWEEN ROCK FRAGMENTS. MINERALIZATION IS NOT PRESENT AS DISSEMINATIONS WITHIN ROCK TYPES EXCEPT FOR PYRITE IN AMPHIBOLITE GNEISSES, AND FOR MINOR DISSEMINATED MOLYBDENITE IN FRAGMENTS OF SNOW CREEK PORPHYRY AT THE EAST SIDE OF THE BRECCIA.? (CROWLEY, 1970)
Deposit ELLIPTICAL DEPOSIT WAS 600 FEET LONG BY 400 FEET WIDE AND MINED TO A DEPTH OF 150 FEET (ROBERTSON, 1951)

Reporter information

Type Date Name Affiliation Comment
Reporter 01-OCT-1976 Krohn, Douglas H. U.S. Geological Survey

Beyond USGS

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

External references

Maps centered on this site