The Bernard Mountain Prospect is a chromium mine located in Alaska.
About the MRDS Data:
All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.
Mine Info
Bernard Mountain Prospect MRDS details
Site Name
Primary: Bernard Mountain Prospect
Secondary: Red Mountain
Commodity
Primary: Chromium
Tertiary: Platinum
Tertiary: Nickel
Location
State: Alaska
District: Tonsina
Land Status
Not available
Holdings
Not available
Workings
Not available
Ownership
Not available
Production
Not available
Deposit
Record Type: Site
Operation Category: Prospect
Operation Type: Unknown
Years of Production:
Organization:
Significant: N
Deposit Size: S
Physiography
Not available
Mineral Deposit Model
Not available
Orebody
Form: LENSE
Structure
Type: R
Description: Area Cut By Three Major Faults; Bernard Mt. Fault, Kimball Pass Fault And One Cross Fault
Alterations
Alteration Type: L
Alteration Text: Serpentinization Widespread In Ultramafices
Rocks
Not available
Analytical Data
Analytical Data: TABLE CONCENTRATES FROM COMPOSITE OF CUT SAMPLES CONTAINED 48% CHROMITE WITH CR: FE RATIO OF 2.7, USBM IC 8626, P. 18
Analytical Data: RANGE: 1500 PPM TO MORE THAN 5000 PPM CR, 1500 PPM TO 5000 PPM NI, MEAN: 5000 PPM CR, 2000 PPM NI, MAXIMUM PT CONCENTRATION .200 PPM, AVERAGE PT CONCENTRATION .023 PPM, HOFFMANN, BARRY, 1974, UNIV. OF ALASKA M. S. THESIS, P. 46, 50
Materials
Ore: Chromite
Comments
Comment (Commodity): ANOMALOUS IN PLATINUM GROUP ELEMENTS, NI AND CU
Comment (Location): LOCATION APPROXIMATED FROM USGS OFR 80-892B, LOC. 42
Comment (Geology): BERNARD MT. IS PART OF A SERPENTINIZED DUNITE SILL THAT EXTENDS DISCONTINUOUSLY OVER 12 MI BY 1.5 MI AREA THAT ROUGHLY PARALLES THE TRACE OF THE BERNARD MT. FAULT; DUNITE AND ASSOCIATED ULTRAMAFICS IN BERNARD MT. AREA ARE INTRUDED INTO ROCKS CORRELATIVE WITH STRELNA FORMATION; N OF BERNARD MT. ULTRAMAFIC BODY STRELNA FORMATION ROCKS ARE INTRUDED BY TWO SMALL BODIES OF AMPHIBOLITE AND GRANULITE GNEISS CUT BY APLITE DIKES; ROCKS OF STRELNA ARE METAMORPHOSED TO LOW GREENSCHIST FACIES. STREINA FM (MISS-PERM) IS SLATE AND PHYLLITE WITH MINOR GRAYWACKE, GREENSTONE, ARKOSIC SANDSTONE, MARBLE.
Comment (Deposit): DESPITE PROXIMITY TO RICHARDSON HIGHWAY, SUFFICIENT QUANTITIES OF ORE GRADE CHROMITE HAVE NOT BEEN PROVEN AND AREA REMAINS UNECONOMIC; MIGHT BE MINED UNDER VERY UNUSUAL ECONOMIC CONDITIONS; SEE ALSO: DUST MOUNTAIN, SHEEP MOUNTAIN ; INFO.SRC : 1 PUB LIT; 2 UNPUB REPT
Comment (Development): USGS BEGAN INVESTIGATING AREA IN EARLY 1930'S; MOST OF BERNARD MT.AREA STAKED FOR CHROMITE BY EARLY 1960'S; GEOLOGICAL, GEOCHEMICAL AND GEOPHYSICAL EXPLORATION MOSTLY AFTER 1960; ALSO SOME TRENCHING, STRIPPING AND SYSTEMATIC SAMPLING; CLAIMS RESTAKED IN 1966; 81 UNPATENTED CLAIMS HELD IN EARLY 70'S
Comment (Deposit): LAYERS, LENSES AND DISSEMINATIONS OF CHROMITE IN DUNITE AND ASSOCIATED ULTRAMAFICS; CHROMITE OCCURS AS DISSEMINATED GRAINS THAT FORM 0.5 TO 1% OF DUNITE, OR AS CONCENTRATIONS OF FROM 2 TO 40% CHROMITE IN TRAINS SEVERAL GRAINS WIDE, MASSIVE LENSES, OR LAYERS UP TO 6 IN THICK
References
Reference (Deposit): USBM IC 8626, P. 18
Reference (Deposit): HOFFMANN, BARRY, 1974, GEOLOGY OF THE BERNARD MOUNTAIN AREA, TONSINA, ALASKA: COLLEGE, ALASKA, UNIVERSITY OF ALASKA M. S. THESIS, 68 P.
Reference (Deposit): USGS OFR 78-1-E, P. 19
Reference (Deposit): USGS MF-438, LOC. 51
Reference (Deposit): USGS OFR 80-892B, LOC. 42
Reference (Other Database): BAG-OFR-80-892B-42
Reference (Deposit): USGS BULL 1246, P. 49, 52
Reference (Deposit): ADGGS GC 15, P. 2, 4
The Top Ten Gold Producing States
These ten states contributed the most to the gold production that built the West from 1848 through the 1930s. The Top Ten Gold Producing States.
