Muscovite Mine

Site Name

Primary: Muscovite Mine

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Commodity

Primary: Mica
Primary: Beryllium
Tertiary: Uranium

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Location

State: Idaho
County: Latah
District: Avon Mining District

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Land Status

Land ownership: Private
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: Patented

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Workings

Type: Surface/Underground

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Ownership

Owner Name: Slette, Orville

Owner Name: Idaho Beryllium And Mica Corp.

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Production

Year: 1910
Time Period: 1888-1910
Description: Hand Cobbed Mica, 1888-1910 725700 Kilograms
Year: 1942
Time Period: 1911-1942
Description: Hand Cobbed Mica, 1911-1942 Few T Be, Carloads Mica
Year: 1945
Time Period: 1943-1945
Description: Beryl Production, 1943-1945 453 Kilograms
Year: 1954
Time Period: 1946-1954
Description: Beryl Production, 1946-1954 2100 Kilograms
Year: 1959
Time Period: 1955-1959
Description: Beryl Production, 1955-1959 729 Kilograms

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Deposit

Record Type: Site
Operation Category: Past Producer
Operation Type: Surface-Underground
Mining Method: Open Stope - Room and Pillar
Milling Method: Handsort
Year First Production: 1888
Discovery Year: 1888
Years of Production:
Organization:
Significant: Y
Deposit Size: M

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Physiography

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

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Mineral Deposit Model

Not available

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Orebody

Form: LENS, TABULAR, PIPELIKE

Form: PEGMATITE

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Structure

Type: L
Structure: Close Folds In Bedding And Schistosity

Type: R
Structure: Steeply Dipping W Limb Of Anticline Of Great Width

Type: R
Structure: Belt Supergroup

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Alterations

Alteration Type: L
Alteration: Tourmalinization

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Rocks

Role: Host
Age Type: Host Rock Unit
Age Young: Neoproterozoic

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Analytical Data

Analytical Data: 0.028 TO 1.4% BE IN 1942 SPECTROGRAPHIC ANALYSIS. PARTS OF SMALLER ZONES EST TO CONTAIN 25-35% BERYL. BRYANT (1939) COMPOSITE PEGMATITE SAMPLE: 84.6% SIO2, 6.1% AL2O3, 6.65% K2O, NA2O, 1.8% FEO, 0.58% BEO, 0.27 CA

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Materials

Ore: Beryl
Ore: Muscovite
Gangue: Apatite
Gangue: Biotite
Gangue: Hematite
Gangue: Limonite
Gangue: Quartz
Gangue: Tourmaline

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Comments

Comment (Production): HISTORY OF PRODUCTION: HPUNI IS "A FEW TONS BERYL AND SEVERAL SEVERAL CARLOADS MICA. STERRETT IN STOLL, 1950.

Comment (Reserve-Resource): RESERVES BELOW # 4 LEVEL (STOLL, 1950). RESERVES ABOVE #4 LEVEL (STOLL, 1950). RESERVES IN OLD MINE DUMPS (PATTEE. ET. AL., 1968). RESERVES FOR THE ENTIRE DEPOSIT.

Comment (Workings): UNDERGROUND WORKINGS CONSIST OF 2 ADITS AND 3 LEVELS.

Comment (Geology): THREE MAJOR BODIES, THE EAST, WEST, AND CENTRAL PEGMATITES, PLUS NUMEROUS SMALLER LENSES HAVE BEEN MINED

Comment (Development): WORKINGS ON PATENTED CLAIM ; ECON.COM: CRYSTALS TOO SMALL, TOO FRACTURED. HEAVY TIMBERING REQUIRED IN CLAYEY GROUND

Comment (Location): ON AND NEAR CREST OF LONG RIDGE THAT EXTENDS S FROM MICA MTN

Comment (Production): MUCH GOOD GRADE BOOK MICA PRODUCED ALL RUBY-STAINED OR BETTER

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References

Reference (Deposit): ANDERSON, A.L., MICA DEPOSITS OF LATAH COUNTY, IDAHO, IDAHO BUREAU OF MINES AND GEOL. PAMP. 14, P.8, 1923

Reference (Deposit): STERRETT, D.B., MICA DEPOSITS OF THE UNITED STATES U.S.G.S. BULL. 740, P. 89, 1923.

Reference (Deposit): STOLL, W.D., MICA AND BERYL PEGMATITES IN IDAHO AND MONTANA, U.S.G.S. PROF. PAPER 229, P.37, 1950.

Reference (Reserve-Resource): STOLL. W.D., MICA AND BERYL PEGMATITES IN IDAHO AND MONTANA, U.S.G.S. PROF. PAPER 229, P. 46-48, 1950.

Reference (Reserve-Resource): FINAL REPORT, MUSCOVITE MINE (MICA) D.M.E.A. DOCKET NUMBER 2607, LATAH CO., IDAHO (CONFIDENTIAL).

Reference (Reserve-Resource): STOLL, W.D., MICA AND BERYL PEGMATITES IN IDAHO AND MONTANA U.S.G.S. PROF. PAPER 229, P.46-48, 1950.

Reference (Reserve-Resource): USBM RI 7148, P. 38, 1968.

Reference (Deposit): PATTEE, E.C., RONALD M. VAN NOY, AND ROBERT D. WELDIN, BERYL RESOURCES OF IDAHO, WASHINGTON, MONTANA, AND OREGON USBM RI 7148, P. 28-39, 1968.

Reference (Deposit): RANEY, RUSSELL G., MUSCOVITE MINE, LATAH COUNTY, IDAHO. MAS PROPERTY EVALUATION FILE REPORT (BERYLLIUM) CONFIDENTIAL UNPUBLISHED REPORT, MAY, 1983.

Reference (Deposit): U.S.G.S. PROF PAPER 229. P. 36-49, 1950.

Reference (Deposit): 1923 RECON D.B. STERRETT, BULL. 740

Reference (Deposit): 1925 RECON IDAHO BUREAU OF MINES AND GEOLOGY PAMPH 14

Reference (Deposit): 1942 GEOLMAP L.R. PAGE, DETAILED SURVEY

Reference (Deposit): 1943 GEOLMAP W.C. STOLL, PROF. PAPER 229

Reference (Deposit): 1957 OTHER IDAHO BUREAU OF MINES AND GEOLOGY CO. REPT. 2

Reference (Deposit): 1959 RECON IDAHO BUREAU OF MINES AND GEOLOGY OPEN-FILE REPT.

Reference (Deposit): HUBBARD, C.R., 1957, MINERAL RESOURCES OF LATAH COUNTY: IDAHO BUREAU OF MINES AND GEOLOGY

Reference (Deposit): CHOATE, R., 1959, IDAHO BUREAU OF MINES AND GEOLOGY OPEN-FILE REPT, 3 P.

Reference (Deposit): BRYANT, B.L., 1939, CONCENTRATION OF LATAH COUNTY BERYL: MOSCOW, IDAHO, UNIVERSITY OF IDAHO, MS THESIS, 15 P.

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Idaho Gold

"Where to Find Gold in Idaho" looks at the density of modern placer mining claims along with historical gold mining locations and mining district descriptions to determine areas of high gold discovery potential in Idaho. Read more: Where to Find Gold in Idaho.