Montgomery Prospect

Prospect in Boundary county in Idaho, United States with commodities Copper, Nickel, Zinc, Cobalt, Gold, Lead
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. Host and associated rocks
  10. Nearby scientific data
  11. Geologic structures
  12. Ore body information
  13. Controls for ore emplacement
  14. Economic information about the deposit and operations
  15. Mining district
  16. Mineral rights holdings
  17. Land status
  18. Ownership information
  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 10067859
MRDS ID W000731
MAS/MILS ID 0160210006
Record type Site
Current site name Montgomery Prospect

Geographic coordinates

Geographic coordinates: -116.38607, 48.95547 (WGS84)
Elevation 945
Relative position NEAR COPELAND AND ABOUT 20 MI N OF BONNERS FERRY. 6 MILES SE OF PORTHILL.

Site location context

Political divisions (FIPS codes)

Boundary(county)

Idaho(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Copeland(quadrangle 1:24,000 scale)

Bonners Ferry(quadrangle 1:100,000 scale)

Sandpoint(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Lower Kootenai(hydrologic unit)

Kootenai(hydrologic accounting unit)

Kootenai-Pend Oreille-Spokane(hydrologic subregion)

Pacific Northwest(hydrologic region)

Federal lands

Idaho Panhandle National Forests(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State County
United States Idaho Boundary

Public Land Survey System information

Meridian Township Range Section Fraction State
Boise 065N 001E 30 NENESW Idaho

Comments on the location information

  • Western Base Of Hall Mountain

Commodities

Commodity Importance
Copper Primary
Nickel Critical Primary
Zinc Critical Tertiary
Cobalt Critical Tertiary
Gold Tertiary
Lead Tertiary

Materials information

Materials Type of material
Chalcopyrite Ore
Gersdorffite Ore
Pentlandite Ore
Sphalerite Ore
Hypersthene Gangue
Pyrite Gangue
Pyrrhotite Gangue
Quartz Gangue
Siderite Gangue

Alteration

  • (Local) Chlorite, Fe Stains
  • (Local) MODERATE

Analytical data

Result AVERAGE GRADE OF 7 LBS CU, 5 LBS NI PER TON. DRILL CORE ASSAYS: 3.5% CU, 1.1%NI. ANALYSIS BY BRACHEBUSCH ON PYRRHOTIZED SILL ROCK: 200 PPM NI.

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite
    Rock unit name Purcell Sill-Uralite-Diorite;;Kaniksu Batholith-Granite To Granodiorite
    Rock description Purcell Sill-Uralite-Diorite;;Kaniksu Batholith-Granite To Granodiorite
    Stratigraphic age (youngest) Neoproterozoic
    Stratigraphic age (youngest) Neoproterozoic
    Stratigraphic age (youngest) Neoproterozoic
  • Host or associated Host
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite
  • Host or associated Host
    Rock type Metamorphic Rock > Metasedimentary Rock > Quartzite
    Rock unit name Prichard Formation-Argillaceous Quartzite
    Rock description Prichard Formation-Argillaceous Quartzite

Nearby scientific data

(1) -116.38607, 48.95547

Economic information

Geologic structures

Type of structure Regional
Structure description Occurrence On East-Dipping Limb Of Large Fold With North-Trending Axis;Kaniksu Batholith,Purcell Trench;Moyie-Leonia Fault
Type of structure Local
Structure description North-Northeast Trending Purcell Sills;Vein On Contact Of Sill With Quartzite

Ore body information

  • Strike N 15-30 DEG W
    Dip 25-40 DEG NE
    Length 457.2M
    Width 24.38M

Controls for ore emplacement

  • Contact Sill
  • IGNEOUS
  • LITHOLOGY

Comments on the geologic information

  • Geol.Desc: Disseminated Sulfides In Mafic Sill, 250 Ft. Thick And Composed Of Hypersthene Gabbro And Uralitized Diorite; Disseminations Of Pyrrhotite And Minor Pentlandite And Chalcopyrite In Its Lower 80 Ft.
  • A Petrographic Study Of A Suite Of Samples Taken From The Ore Body Show The Average Density (From Six Samples) To Be 2.985 Grams Per Cubic Centimeter. The Aldridge-Prichard Formation, Of The Precambrian Belt Series Is Intruded By Numerous Diorite And Gabbro Sills Some Of Which Are As Much As 600 Meters Thick.
  • Eight Samples Were Taken Whose Assays Averaged 0.56 Percent In Copper, 0.06 Percent In Nickel, And 0.25 Ounces Of Gold Per Ton. Cobalt Was Not Included In The Assays.
  • The Three Upper Adits Explore A Quartz Vein In Or Near The Footwall Of A Large Basic Sill. It Was Found To Contain Minor Amounts Of Iron, Lead, And Zinc Sulfides, But In No Place Were The Minerals Sufficiently Concentrated To Even Approach A Commercial Grade. The Lower Tunnels Cut Several Minor Slips And Seams, But No Definite Vein. Instead The Walls Are Heavily Pyrhotitized And Appear To Be Components Of An Extensive Low Grade Ore Body. Microscopic Evidence Indicates That The Sulfides Of The Sill Rock Are The Result Of Concentration By Magmatic Segregation The Evidence That Is Common To All Of The Sulfide-Bearing Samples Includes The Following: Igneous Textures, Inclusion Of Sulfides Within Silicates With The Distinct Corrosion Of The Silicates Along Cleavage Planes And Planes Of Weakness By The Sulfides, And No Apparent Corrosion Of The Sulfides By The Silicates. The Corrosion Of The Silicates By The Sulfides May Be Explained As Follows: During The Latter Stage Of Crystal- Ization All Of The Silicates Were Crystalized While The Sulfides Were Still Molten Due To Their Lower Melting Point. The Sulfides, Descending As Immiscible Droplets To The Base Of The Sill, Were Crystalized And Deuterically Replaced Silicate Minerals. Varying Degrees Of Hydrothermal Alter- Ation Subsequently Produced Sericite And Kaolinite At The Expense Of The Feldspar.

Economic information about the deposit and operations

Operation type Underground
Development status Prospect
Commodity type Metallic
Deposit size Small
Significant No

Mining district

District name Moyie-Yaak District

Mineral rights holdings

Type of mineral rights Located Claim

Land status

Ownership category National Forest
Area name Kaniksu National Forest

Ownership information

  • Type Owner
    Owner Montgomery Mines, Inc.
    Home office Idaho
    Year 1953
  • Type Operator
    Owner M. N. Seeley
    Home office Wyoming
    Year 1953

Comments on the reserve resource information

  • Marginal Cu-Ni Ore Reserves Indicated Because Of Low Tenor
  • Reserves Insignificant Because Of Low Tenor.

Workings at the site

  • Type of workings Underground
    Length 975.36M

Comments on the workings information

  • 7 Tunnels

Comments on development

  • 68 Unpatented Claims. Three 30-Ft Ddhs

Reference information

Bibliographic references

  • Deposit

    Brackebusch,Fred W.,1969,Economic Geology Of The Queen Mountain Area, A Part Of The Purcell Range, Boundary County,Idaho: Unpublished Thesis,Univ.Idaho,76p.

  • Deposit

    Cornwall, H.R., 1966, Nickel Deposits Of North America: USGS Bulletin 1223, 62 P.

  • Deposit

    Kiilsgaard,Thor H.,1951,Description Of Some Ore Deposits And Their Relationships To The Purcell Sills, Boundary County,Idaho:Idaho Bureau Of Mines And Geology Pamph; No. 85, 31p.

  • Deposit

    Lemoine,Denis,1959,Thorite Deposits And General Geology Of The Hall Mountain Area,Boundary County,Idaho:Unpublished Thesis,Univ.Idaho, 68p.

  • Deposit

    5) Spokane Chronicle, Mar. 23, 1974; Feb. 14, 1974.

  • Deposit

    6) Western Mining News, 1974-75 Directory Of Mines In Idaho (Coeur D'Alenes) And Washington, P. 89.

  • Deposit

    1951 Compile Idaho Bureau Of Mines And Geol. Pamph No. 85

  • Deposit

    1966 Cornwall,H.R., Bulletin1223

  • Deposit

    1973 Direxpl Montgomery Mines

  • Reserve-Resource

    Cornwall, H.R., 1966, USGS Bulletin 1223, P. 42.

  • Deposit

    U.S.Bureau Of Mines, Wfoc, Mineral Property File 0160210006.

General comments

Subject category Comment text
Deposit 3-4 Anomalies
Deposit Amount Of Sulfide-Bearing Rocks Is Large, But The Tenor Of Nickel And Copper Is Too Low To Be Of Economic Interest, 1974 Drilling Indicated An 80-Ft-Wide Zone Averaging 7lbs Cu And 5lbs Ni/Ton, And Indications Of About $5/Ton Au Values.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-JUL-1972 Coury, Anny B. U.S. Geological Survey
Updater 01-SEP-1976 Miller, Pat J. U.S. Geological Survey
Reporter 02-OCT-1990 Kauffman, John D. U.S. Bureau of Mines

Beyond USGS

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

External references