Zortman Mine

The Zortman Mine is a gold mine located in Phillips county, Montana at an elevation of 4,600 feet.

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

Satelite View

MRDS mine locations are often very general, and in some cases are incorrect. Some mine remains have been covered or removed by modern industrial activity or by development of things like housing. The satellite view offers a quick glimpse as to whether the MRDS location corresponds to visible mine remains.

Site Name

Primary: Zortman Mine
Secondary: Zortman-Landusky Mine and Plants
Secondary: August Mine
Secondary: Little Ben
Secondary: Rudy Gulch Mine
Secondary: Zortman
Secondary: Zortman Extension
Secondary: Landusky
Secondary: Independent
Secondary: Alabama
Secondary: Gold Bug

Commodity

Primary: Gold
Tertiary: Silver

Location

State: Montana
County: Phillips

Land Status

Land ownership: Unknown
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.

Holdings

Type: Located Claim
Type: Patented

Workings

Type: Surface

Ownership

Owner Name: Pegasus Gold Inc.
Company ID: 2400539
Percent: 100.0
Home Office: Washington
Info Year: 1995

Production

Year: 1995
Mined: 9090000.000 mt
Description: Gold Production 110900 T Oz/Yr Gold
Year: 1994
Mined: 13430000.000 mt
Description: Mill Feed @ .58 Gm Au, 4.3 Gm Ag 13430000 Mt Ore
Year: 1993
Mined: 11340000.000 mt
Description: Mill Feed @ .58 Gm Au, 5.9 Gm Ag 11340000 Mt Ore
Year: 1991
Mined: 12916000.000 mt
Description: Mill Feed @ .62 Gm Au, 9.2 Gm Ag 12916000 Mt Ore
Year: 1992
Mined: 11770000.000 mt
Description: Mill Feed @ .51 Gm Au, 8.2 Gm Ag 11770000 Mt Ore
Year: 1990
Mined: 11812000.000 mt
Description: Mill Feed @ .55 Gm Au, 6.9 Gm Ag 11812000 Mt Ore
Year: 1989
Mined: 9119000.000 mt
Description: Mill Feed @ 9119000 Mt Ore
Year: 1987
Mined: 8766000.000 mt
Description: Mill Feed @ Mt Ore
Year: 1988
Mined: 10410000.000 mt
Description: Mill Feed @ Mt Ore
Year: 1986
Mined: 5914000.000 mt
Description: Mill Feed @ 0.651 G Au 5914000 Mt Ore
Year: 1985
Mined: 4808000.000 mt
Description: Mill Feed @ 0.72 Gm, Au 6.86 Gm Ag 4808000 Mt Ore
Year: 1984
Mined: 5171000.000 mt
Description: Mill Feed @ 0.79 Gm Au, 6.86 Gm Ag 5171000 Mt Ore
Year: 1982
Mined: 3116000.000 mt
Description: Same As Above 3116000 Mt Ore
Year: 1983
Mined: 3654000.000 mt
Description: Mill Feed @ 1.13 Gm Au, 6.86 Gm Ag 3654000 Mt Ore
Year: 1981
Mined: 1857000.000 mt
Description: Same As Above 1857000 Mt Ore
Year: 1980
Mined: 1170000.000 mt
Description: Same As Above 1170000 Mt Ore
Year: 1979
Mined: 651000.000 mt
Description: Mill Feed @ 1.03 Gm Au, 2.06 Gm Ag 651000 Mt Ore

Deposit

Record Type: Site
Operation Category: Past Producer
Deposit Type: Au-Ag-Te vein
Plant Type: Leach
Plant Subtype: Hydromet
Operation Type: Surface
Mining Method: Open Pit
Milling Method: Heap Leach-Carbon Column-Merrill-Crowe
Year First Production: 1979
Discovery Year: 1975
Discovery Method: Ore-Mineral In Place
Years of Production:
Organization:
Significant: Y
Deposit Size: S

Physiography

General Physiographic Area: Interior Plains
Physiographic Province: Great Plains Province
Physiographic Section: Missouri Plateau, Unglaciated

Mineral Deposit Model

Model Name: Alkaline Au-Te (Au-Ag-Te veins)

Orebody

Not available

Structure

Not available

Alterations

Not available

Rocks

Name: Syenite
Role: Host
Age Type: Associated Rock
Age Young: Tertiary

Name: Quartz Monzonite
Role: Host
Age Type: Host Rock
Age Young: Tertiary

Analytical Data

Not available

Materials

Ore: Sylvanite
Ore: Silver
Ore: Gold
Ore: Hessite
Ore: Calaverite
Ore: Sphalerite
Ore: Pyrite
Gangue: Fluorite
Gangue: Calcite

Comments

Comment (Deposit): THE GOLD IS BELIEVED TO BE DERIVED FROM A MAGMATIC SOURCE, DEPOSITED IN MAJOR SHEAR ZONES AND FRACTURES AT HIGHER LEVELS OF THE INTRUSIVE COMPLEX. (HASTINGS, 1988).; STRUCTURALLY CONTROLLED EPITHERMAL SYSTEMS (STOCKWORKS, BRECCIAS, FRACTURED `SHEETED? ZONES) (FROM A SUMMARY PROVIDED BY PEGASUS GOLD CORP., MBMG FILES)

Comment (Production): PRODUCTION FROM 1884 TO 1985 ESTIMATED AT: 727,414 OZ AU 789,000 OZ AG; PRODUCTION FROM 1903 TO 1950 FROM THE RUBY GULCH PROPERTY (ZORTMAN SIDE) EST. AT: 270,OOO OZ AU, 3,000,000 OZ AG (FROM THE MINING RECORD, MAY 6, 1992); FROM THE LANDUSKY SIDE FROM 1907 TO 1942: 120,150 OZ AU, 3,782,500 OZ AG BULK-MINEABLE; HEAP-LEACH. PRODUCTION REPORTED BY VARIOUS SOURCES: 1980-34,000 OZ AU, 52,000 OZ AG, AVE. 0.31 OPT AU FROM 1,411,000 SHORT TONS MINED. 1981-38,000 OZ AU, 104,000 OZ AG, AVE. 0.26 OPT AU FROM 2,163,000 SHORT TONS MINED. 1982-67,000 OZ AU, 145,000 OZ AG, AVE. 0.037 OPT AU FROM 3,873,000 SHORT TONS MINED. 1983-77,000 OZ AU, 175,000 OZ AG 1984-70,000 OZ AU, 152,000 OZ AG. 1986-92,000 OZ AU, 218,000 OZ AG 1988-106,000 OZ AU, 218,000 OZ AG

Comment (Deposit): Merged data from deposit ID10149096 (Landusky)

Comment (Production): HEAP LEACHING OPERATION. 1988 AU PROD.= 90,000 OZ., 1989 AU PROD.= 106,400 OZ. AU FROM 9,161,000 MT ORE LEACHED. 1989 RESERVE = 765,000 OZ. CONT. AU. THREE-FOUR WINTER MONTHS LOST TO PRODUCTION DUE TO INCLEMENT WEATHER.

Comment (Deposit): INCLUDES THREE DISTINCT MINES, OWNED AND OPERATED BY ZORTMAN & LANDUSKY. THEIR PRODUCTION IS POOLED AND THE COMPANIES OPERATE A JOINT OFFICE. ZORTMAN & LANDUSKY ARE SUBSIDS. OF PEGASUS GOLD CORP. MINES ARE: AUGUST MINE: BOM SEQ# 0300710051: MSHA MINES ID #2401150 LITTLE BEN: BOM SEQ# 0300710018: NO MSHA MINES ID# RUDY GULCH MINE: BOM SEQ# 0300710004: MSHA MINES ID #2401450 THE ZORTMAN EXTENSION PROJECT IS IN NORTH-CENTRAL MONTANA AND 1.4 MILLION OUNCES OF GOLD (60 MILLION TONNES GRADING .71G/T) IN PROVEN AND PROBABLE RESERVES. THE PERMITS WILL ALLOW THE COMPANY TO MINE 72 MILLION TONNES OF ORE AND THE ASSOCIATED 54 MILLION TONNES OF WASTE ROCK. UNDER THE APPROVED MINE PLAN ORE WILL BE CONVEYED TO A NEW HEAP LEACH FACILITY ON GOSLIN FLATS FOR TREATMENT AND WASTE ROCK WILL BE PLACED IN AN AREA, MUCH OF WHICH HAS PREVIOULSLY BEEN DISTURBED BY ZORTMAN OPERATIONS. CAPITAL FOR THE EXTENSION PROJECT IS PRESENTLY EXTIMATED AT $50 MILLION. MINING CEASED IN JAN 96 UNTIL DECISION OF ZORTMAN EXT CAN BE MADE BY 3 QRT 96, EXPECT + DECISION ON EXT. THE LANDUSKY CLOSED IN 1994: ONLY THE ZORTMAN AND ZORTMAN EXT WILL REOPEN SOME TIME IN 1998.

Comment (Economic Factors): THERE ARE NO MINE EQUIPMENT OR EQUIPMENT CAPITAL COSTS BE- CAUSE ACTUAL MINING IS CONTRACTED OUT. INVESTMENT SHOWN DOES NOT INCLUDE PROPOSED SIX MILLION MINE CAPITAL THAT MAY BE SPENT ON UPGRADING MINING CAPABILITY TO EXPLOIT SULPHIDE ORE UNDERLYING OXIDES. WORK DUE 1993-1995. THERE ARE TWO SEPARATE OPEN PIT AND HEAP LEACH OPERATIONS;

Comment (Reserve-Resource): RESERVES, PROVEN + PROBABLE 12/31/96, TOTAL ZORTMAN INCLS EXT. MINE CEASED OPERATION IN JAN 96 UNTIL DECISION OF ZORTMAN EXT CAN BE MADE. THE ZORTMAN SHOULD START UP IN 1998:

Comment (Reserve-Resource): THE OXIDE ORE RESERVES GIVE THE OPERATION AN ADDITIONAL FOUR YEARS OF MINE LIFE. BECAUSE OF TOPOGRAPHIC RESTRAINTS, AND BECAUSE THE OXIDE ORE IS DIRECLTY UNDERLAIN BY THE SULFIDE ORE, NO INFERRED ORE RESOURCES HAVE BEEN ESTIMATED. PEGASUS DID NOT MAKE DRILL DATA AVAILABLE TO THE AUTHOR. IT WAS THEREFORE IMPOSSIBLE TO DETERMINE INFERRED RESOURCES FOR THE POTENTIALLY AVAILABLE NONOXIDE RESERVES. PUBLISHED RESERVES: OXIDE - 45,600,000 ST @ 0.015 OZ/ST AU SULFIDE - 56,800,000 ST @ 0.019 OZ/ST AU 1992 RESERVES FROM RANDOL 1993/94. 1995 RESERVES FROM PEGASUS 10-K REPORT, 12-94.

Comment (Economic Factors): DORE BULLION IS SHIPPED TO HANDY AND HARMAN IN ANAHEIM, CA., BY PLANE.

Comment (Ownership): THE RUBY GULCH MINE IS OPERATED BY THE ZORTMAN MINING CO. THE AUGUST, AND LITTLE BEN MINES ARE OPERATED BY THE LANDUSKY MINING CO. BOTH ZORTMAN AND LANDUSKY MINING COMPANIES ARE OWNED BY PEGASUS GOLD CORP. OF VANCOUVOR, B.C. CANADA. THE ZORTMAN MINING COMPANY AND THE LANDUSKY MINING COMPANY ACT AS ONE MINING COMPANY WITH OFFICES AND FIRE REFINERY IN ZORTMAN, MT.

Comment (Geology): MINERALIZATION WAS ORIGINALLY SULFIDES, WITH PYRITE DOMINANT AND WITH MINOR ARSENOPYRITE, MARCASITE AND COVELLITE. THE GOLD OCCURRED WITH THE PYRITE. OXIDATION EXTENDS TO 200 MTRS OR MORE IN DEPTH, WITH SULFIDES OCCURRING BELOW THIS. THE GRADE OF THE OXIDE ZONE AVERAGES 0.65 GM/MT AU. THE SULFIDES AVERAGE 2.80 GM/MT AU. SILVER IS ASSOCIATED WITH THE GOLD AND OCCURS AT A RATIO 2:1 SILVER TO GOLD.

References

Reference (Reference): Wilson M R, Kyser T K 1988 - Geochemistry of porphyry-hosted Au-Ag deposits in the Little Rocky Mountains, Montana: in Econ. Geol. v83 pp 1329-1346

Reference (Deposit): HASTINGS, J.S. GOLD DEPOSITS OF ZORTMAN-LANDUSKY, LITTLE ROCKY MOUNTAINS, MONTANA. IN: BULK MINEABLE PRECIOUS METAL DEPOSITS OF THE WESTERN UNITED STATES SYMPOSIUM PROCEEDINGS. GEOL. SOC. OF NEVADA, RENO, NV, 1988, PP 187-205.

Reference (Deposit): ROGERS, LESLIE M., AND M. STEPHEN ENDERS. SYENITE-HOSTED GOLD DEPOSITS OF THE LITTLE ROCKY MOUNTAINS, MONTANA. IN: CASE HISTORIES OF MINERAL DISCOVERIES, V. 2., DISCOVERIES OF VALUABLE MINERALS AND PRECIOUS METALS DEPOSITS RELATED TO INTRUSIONS AND FAULTS. V.E. HOLLISTER, ED., SME-AIME, 1990, PP. 117-130.

Reference (Deposit): CROWHURST, J.J. DISCOVERY AND DEVELOPMENT OF THE PEGASUS OPERATION AT ZORTMAND AND LANDUSKY, PHILLIPS COUNTY, MONTANA IN: CASE HISTORIES OF MINERAL DISCOVERIES, V. 2, DISCOVERIES OF VALUABLE MINERALS AND PRECIOUS METALS DEPOSITS RELATED TO INTRUSIONS AND FAULTS. V.F. HOLLISTER, ED., SME-AIME, 1990, P. 117.

Reference (Deposit): MONT. BUREAU OF MINES AND GEOL. BULLETIN 129, 1991

Reference (Deposit): COMPANIES. ZORTMAN-LANDUSKY MINE, 1990, PP. 43, 189.

Reference (Deposit): RANDOL MINING DIRECTORY. 1990/1991. U.S. MINES AND MINING

Reference (Deposit): MCCULLOCH, ROBIN. UNPUBLISHED DATA ON THE ZORTMAN-LANDUSKY PROPERTY, FEB. 1991, 1 P.

Reference (Deposit): MONTANA STANDARD. TOP CYANIDE LEACHING SITES LISTED. APT. 10, 1990. UNKNOWN P.

Reference (Reserve-Resource): PLEXUS GOLD IN. 1985 ANNUAL REPORT.

Reference (Reference): CANADIAN MINES HANDBOOK 1981-82, P. 277.

Reference (Reference): WORLD MINING, SEPT. 1982, P. 71.

Reference (Reference): ZORTMAN MINING CO. AND LANDUSKY MINING CO., PHILLIPS CO., MONTANA (UNDATED).

Reference (Deposit): BROOK HUNT & ASSOCIATES LTD. INDEPENDENT RESEARCH INTO METAL AND MINERAL RESOURCES AND THEIR MARKETS. 1986, PP. 350-353.

Reference (Deposit): NORTHERN MINER PRESS. AMERICAN MINES HANDBOOK-1990. PP. 148-149.

Reference (Deposit): PEGASUS GOLD INC. FORM 10-K. DEC. 31, 1989.

Reference (Deposit): GOLD. MAY, 1986, 5 PP. REPRINT.

Reference (Reserve-Resource): PEGASUS GOLD INC., 1995 ANNUAL REPORT, PP. 6-7, 11-13.

Reference (Reserve-Resource): MINING RECORD, PEGASUS INCREASES RESERVES 14 PERCENT IN THREE MONTHS, V 106/N 18, 3/29/95, PP. 1, 4.

Reference (Reserve-Resource): PEGASUS GOLD INC., 1995 10-K REPORT, PP. 9, 13-14.

Reference (Reserve-Resource): PEGASUS GOLD INC., 1994 ANNUAL REPORT, P5 & 10-K, PP. 12-13.

Reference (Deposit): E&MJ. THE NEW DRILLING AND BLASTING DIMENSION AT PEGASUS. GOLD. MAY, 1986, 5 PP. REPRINT.

Reference (Deposit): PEGASUS GOLD INC. PEGASUS GOLD REPORTS THIRD QUARTER RESULTS. OLT. 26, 1990, 2. PP.

Reference (Reserve-Resource): PEGASUS GOLD INC., 1996 ANNUAL REPORT, PP. 6-7, & FORM 10-K REPORT, PP. 8, 15-16.

Reference (Deposit): PEGASUS GOLD INC. PROXY STATEMENT. APRIL 27, 1990, 13 PP.

Reference (Deposit): LOEWEN, ONDAATJE, MCCUTCHEN & COMPANY LIMITED. MONITOR REPORT - PEGASUS GOLD INC. MAR. 20, 1990. 8 PP.

Reference (Deposit): ENDAR YEAR 1990, P. 27. ANNUAL REPORT. 49 PP.

Reference (Deposit): PEGASUS GOLD INC. 1988 ANNUAL REPORT. 36 PP.

Reference (Deposit): PEGASUS GOLD INC. CORPORATE PROFILE. SPRING, 1987, 21 PP.

Reference (Deposit): PEGASUS GOLD INC. 1988 CORPORATE PROFILE. 21 PP.

Reference (Deposit): PEGASUS GOLD INC. 1987 ANNUAL REPORT. 37 PP.

Reference (Deposit): PEGASUS GOLD INC. PROSPECTUS (GOLDMAN, SACHS & CO., E.F. HUTTON AND COMPANY INC., PRUDENTIAL-BACHE CAPITAL FUNDING) JULY 20, 1987, 44 PP. PLUS F-53 P. FINANCIAL STATEMENT.

Reference (Deposit): MINE/DEPOSIT FILE REPORT: AUGUST, GOLD BUG, LITTLE BEN, RUBY GULCH MINES, ZORTMAN-LANDUSKY MINING COMPANIES, ZORTMAN, MT, USBM CONTRACT NO. SO221028, APRIL, 1983.

Reference (Deposit): PEGASUS GOLD INC. 1986 ANNUAL REPORT. 41 PP.

Reference (Deposit): PEGASUS GOLD INC. FORM 10-K. DEC. 31, 1985, 65 PP.

Reference (Deposit): PEGASUS GOLD INC. 1985 ANNUAL REPORT. 37 PP.

Reference (Deposit): PEGASUS GOLD INC. FORM 10-K. DEC. 31, 1984, 18 PP.

Reference (Deposit): PEGASUS GOLD LTD. 1983 ANNUAL REPORT. 22 PP.

Reference (Deposit): PEGASUS GOLD INC. 1984 ANNUAL REPORT. P. 12.

Reference (Deposit): MONTANA DEPARTMENT OF STATE LANDS, DRAFT ENVIRONMENTAL IMPACT STATEMENT, PROPOSED PLAN OF MINING AND RECLAMATION, INTERNATIONAL MINING NEWS, VOL., 107, #47, 11/20/96, P1.

Reference (Deposit): THE MINING RECORD, VOL 107, N47, NOV., 20, 1996, P1.

Reference (Deposit): THE MINING RECORD, VOL 83, #18, JUNE 30, 1997, P14.

Reference (Deposit): PEGASUS GOLD NEWS RELEASE, SEPT.30, 1996.

Reference (Deposit): PEGASUS GOLD NEWS RELEASE, JULY 22, 1996.

Reference (Deposit): THE MINING RECORD, VOL., 107, #49, 12/4/96, PP. 8, 9.

Reference (Deposit): BUSINESS WIRE. "ZORTMAN RECEIVES RECORD OF DECISION" 10/28/96. 1P.

Reference (Deposit): RIPLEY, RICHARD. PEGASUS MAY OPEN UNTAPPED GOLD DEPOSITS. SPOKANE JOURNAL OF BUSINESS, NOV. 21, 1990. 2 PP.

Reference (Deposit): GOLD GAZETTE, 7/3/95, P.13.

Reference (Deposit): ENDERS, M.S., AND L.M. ROGERS. DESIGN OF THE GEOLOGIC PROGRAM AT THE ZORTMAND AND LANDUSKY MINES, LITTLE ROCKY MOUNTAINS, MONTANA. SME-AIME PREPRINT NO. 83-373, 9 PP.

Reference (Deposit): PROGRAM AT THE ZORTMAND AND LANDUSKY MINES, LITTLE ROCKY MOUNTAINS, MONTANA. SME-AIME PREPRINT NO. 83-373, 9 PP.

Reference (Deposit): CORRY, A.V., 1933, SOME GOLD DEPOSITS OF BROADWATER, BEAVERHEAD, PHILLIPS, AND FERGUS COUNTIES, MONTANA: MONT. BUREAU OF MINES AND GEOL. MEM. 10, P. 30-36

Reference (Deposit): SPOKANE JOURNAL OF BUSINESS, NOV. 21, 1990. 2 PP.

Reference (Deposit): DAYTON, S.H., 1983, PEGASUS GOLD BUILDING A FUTURE FROM WHAT MAY BE THE WORLD?S LOWEST-GRADE BUT LARGEST HEAP LEACHING OPERATION: ENGINEERING AND MINING JOURNAL, DECEMBER, 1983, P. 24-28.

Principal Gold Districts of Montana

In Montana, 54 mining districts have each have produced more than 10,000 ounces of gold. The largest producers are Butte, Helena, Marysville, and Virginia City, each having produced more than one million ounces. Twenty seven other districts are each credited with between 100,000 and one million ounces of gold production. Read more: Principal Gold Districts of Montana.