Mammoth-Good Hope Mine

The Mammoth-Good Hope Mine is a gold and silver mine located in Gunnison county, Colorado at an elevation of 9,058 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

Name: Mammoth-Good Hope Mine  

State:  Colorado

County:  Gunnison

Elevation: 9,058 Feet (2,761 Meters)

Commodity: Gold, Silver

Lat, Long: 38.34306, -107.00667

Map: View on Google Maps

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Satelite image of the Mammoth-Good Hope Mine

Mammoth-Good Hope Mine MRDS details

Site Name

Primary: Mammoth-Good Hope Mine
Secondary: Good Hope Mine
Secondary: Mammoth Chimney Mine
Secondary: Patented Claims: Vulcan, MS 10909
Secondary: Rose Bud, MS 10910
Secondary: War Eagle, MS 10910
Secondary: Humming Bird, MS 10910
Secondary: Iron Clad, MS 10910
Secondary: Mammoth Chimney, MS 12454
Secondary: Good Hope, MS 12456
Secondary: Humboldt, MS 16392
Secondary: Mill Site Lode, MS 19920
Secondary: Unpatented Claims: Wall Street
Secondary: Camp Bird
Secondary: Sunny Side
Secondary: Last Hope
Secondary: Carberry
Secondary: Spar
Secondary: Little La Veta


Commodity

Primary: Gold
Primary: Silver
Secondary: Sulfur
Secondary: Copper
Tertiary: Tellurium
Tertiary: Lead
Tertiary: Zinc
Tertiary: Selenium
Tertiary: Bismuth
Tertiary: Mercury
Tertiary: Vanadium


Location

State: Colorado
County: Gunnison
District: Domingo (Vulcan) District


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.


Holdings

Not available


Workings

Not available


Ownership

Owner Name: Herron Mining Co.
Years: 1983 -

Owner Name: Webbco, Cleveland, Tx. (Vulcan Resources, Inc., El Paso, Tx)
Years: 1983 -


Production

Year: 1902
Time Period: 1898-1902
Description: Cp_Grade: ^9.19 Oz/Ton Au, 21.89 Oz/Ton Ag


Deposit

Record Type: Site
Operation Category: Producer
Operation Type: Unknown
Year First Production: 1898
Year Last Production: 1983
Discovery Year: 1894
Discovery Method: Ore-Mineral In Place
Years of Production:
Organization:
Significant: N
Deposit Size: S


Physiography

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


Mineral Deposit Model

Not available


Orebody

Not available


Structure

Type: R
Description: Gunnison Uplift, San Juan Volcanic Field

Type: L
Description: Gunnison Gold Belt, Iron Hill Alkalic Complex, Tolvar Peak Stock


Alterations

Alteration Type: L
Alteration Text: Oxidation Of Pyrite To Fe Oxides And Native S; Sericitization And Chloritization Of Schist Near Mineralized Zone; Supergene Alteration Of Cu Sulfide To Covellite; Supergene Alteration Of Tellurides To Native Te And Cu Telluridess (Rickardite, Weissite, Vulcanite)


Rocks

Name: Intrusive Carbonatite
Role: Associated
Age Type: Host Rock
Age Young: Neoproterozoic

Name: Intrusive Carbonatite
Role: Associated
Age Type: Associated Rock
Age Young: Late Cambrian


Analytical Data

Analytical Data: SIXTEEN SAMPLES OF GOSSAN AND CHALCEDONY CONTAINED TRACE TO 0.832 OZ/TON AU (HIGHS OF 4.86, 7.44, 19.51, AND 35.48 OZ/TON AU), 0.05 TO 6.58 OZ/TON AG (HIGHS OF 9.90, 20.98, 45.20, AND 45.69 OZ/TON AG), 100 TO 300 PPM SE, 40 PPM TE, AND 0.2 TO 0.8 PPM HG.
Analytical Data: HARTLEYS (1983) ANALYSES OF 19 SAMPLES OF PYRITE/SPHALERITE, PYRITE/SCHIST, LOOSE PYRITE, AND MASSIVE PYRITE FROM DUMPS CONTAINED TRACE TO 0.05 OZ/TON AU (HIGH OF 0.35 OZ/TON AU), 0.05 TO 0.81 OZ/TON AG (HIGHS OF 1.48 AND 2.00 OZ/TON AG), 1.3 TO 37.5% ZN, 0.02 TO 0.32% CU (HIGHS OF 9.12 AND 17.78% CU), 0 TO 0.60% PB, 5 TO 500 PPM SE, 10 TO 200 PPM TE, 0.4 TO 21 PPM HG.
Analytical Data: SULFUR-SELENIUM LENS AVERAGES 78% S AND 0.59% SE
Analytical Data: TWELVE SAMPLES OF SULFUR AND SULFUR-SELENIUM CONTAINED 0.01 TO 0.24 OZ/TON AU, 0.29 TO 4.00 OZ/TON AG (HIGHS OF 7.02 AND 10.60 OZ/TON AG), 200 TO 8000 PPM SE (HIGH OF 4.2 TO 17% SE FROM SE-RICH S SAMPLE), 4 TO 1660 PPM TE, 16 TO 140 PPM HG.
Analytical Data: TWO OF THESE SAMPLES ALSO CONTAINED 27 AND 19% FE, 70 AND 270 PPM CR, 50 AND 270 PPM MN, 220 PPM AS.


Materials

Ore: Copper
Ore: Sulfur
Ore: Galena
Ore: Chalcopyrite
Ore: Gold
Ore: Rickardite
Ore: Petzite
Ore: Sylvanite
Ore: Sphalerite
Gangue: Tetradymite
Gangue: Quartz
Gangue: Coloradoite
Gangue: Jasper
Gangue: Sericite
Gangue: Chlorite
Gangue: Limonite
Gangue: Roscoelite
Gangue: Pyrrhotite
Gangue: Magnetite


Comments

Comment (Production): PARTIAL PRODUCTION RECORD FOR COMBINED GOOD HOPE AND VULCAN MINES. CDM CITES PRODUCTION FOR 1916 AND 1918, BUT NO FIGURES WERE INCLUDED. PRODUCTION FIGURES FOR 1894 TO 1916 UNAVAILABLE, BUT HARTLEY (1983) CITES CUMULATIVE TONNAGE AND GRADE FOR PERIOD 11/3/98 TO 6/13/02. PRODUCTION FOR 1925 CITED AS CEMENT CU RATHER THAN ACTUAL CONCENTRATES. IN ADDITION TO MATTE SMELTER PROCESSING OF ORE AND DUMP MATERIAL, NELSON REPORTS TREATMENT OF MINE WATER LEACHED FROM OLD STOPES TO RECOVER CU BY PRECIPITATION ON SCRAP IRON. 1983 RECOVERY OF AU WAS BY CYANIDE HEAP LEACHING OF DUMP ORE (AURIFEROUS PYRITE).

Comment (Deposit): MINERALIZATION: (1) STRATIFORM MASSIVE SULFIDE LENS; (2) AU-, AG-, AND CU-TELLURIDE-BEARING CRYPTOCRYSTALLINE SILICA VEIN SYSTEM CONFINED PRIMARILY TO HANGING WALL OF SULFIDE LENS; (3) NATIVE SULFUR/NATIVE SELENIUM LENS ABOVE PRESENT WATER TABLE. MASSIVE SULFIDE LENS TRENDS EAST-WEST, DIPS 80 TO 90 NORTH, AND IS ABOUT 700 FT LONG (ALONG STRIKE), 500 FT DEEP, AND AVERAGES 15 FT THICK; CONSISTS OF STRATIFORM ZONE OF BANDED, RECRYSTALLIZED COARSE-GRAINED PYRITE, SPHALERITE, AND CHALCOPYRITE WITH VARIABLE AMOUNTS OF QUARTZ AND SERICITE. LENS PINCHES OUT DOWNWARD INTO LOW-SULFIDE PYRITIC SERICITIC SCHIST. PETZITE AND SYLVANITE OCCUR AS DISSEMINATED GRAINS IN ZONE OF CRYPTOCRYSTALLINE SILICA (CHALCEDONY AND OPAL) IN QUARTZ-SERICITE SCHIST IN HANGING WALL OF MASSIVE SULFIDE LENS. CHALCEDONY VEINLETS ALSO OBSERVED CUTTING S/SE LENS AND OVERLYING GOSSAN. VEINLETS ALSO CONTAIN NATIVE TE CRYSTALS; TELLURITE, COLORADOITE, TETRADYMITE(?), AND RARE CU TELLURIDES (RICKARDITE, WEISSITE, AND

Comment (Deposit): VULCANITE). VEINLETS ARE UNMETAMORPHOSED AND SHOW DELICATE REPLACEMENT TEXTURES. IN OXIDIZED ZONE ABOVE SULFIDES IS HORIZONTAL, ROD-SHAPED LENS OF NATIVE SULFUR, CONTAINING NATIVE SELENIUM, AND MEASURING 600 FT LONG, 20 FT THICK, AND 20 TO 30 FT WIDE. LENS LIES ABOVE WATER TABLE IN OXIDIZED SECTION OF MASSIVE SULFIDE LENS. BELOW WATER TABLE, SILICA MATRIX HAS BEEN LEACHED TO FORM ZONE OF LOOSE, FLOWING SANDLIKE PYRITE. LENS AVERAGES 78% S AND 0.59% SE, WITH SUBLENSES CONTAINING UP TO 17% SE. GOSSAN CAP DEVELOPED FROM TOP OF LENS TO SURFACE. DEPOSIT WAS ORIGINALLY BELIEVED TO BE VEIN AND CHIMNEY DEPOSIT, WITH NATIVE S RESULTING EITHER BY DOWNWARD DESULFURIZATION OR OXIDATION OF PYRITE OR BY PRECIPITATION FROM LATE-STAGE ASCENDING SULFURATED HYDROGEN GASES. NEWER INTERPRETATION OF SULFIDES IN GUNNISON GOLD BELT SHOWS MASSIVE SULFIDE TO BE SYNGENETIC, SUBMARINE, VOLCANOGENIC EXHALITE. DISTAL ORIGIN OF LENS SUGGESTED BY (1) ENCLOSURE WITHIN VOLCANICS DEPOSITED AT CONSIDERABLE DISTANCE

Comment (Deposit): GEOLOGIC REPORT ON THE VULCAN-ANACONDA-HEADLIGHT MINE AREA, DUBOIS GREENSTONE BELT, GUNNISON COUNTY, COLORADO: UNPUB. REPT. ; INFO.SRC : 1 PUB LIT; 2 UNPUB REPT; 3 FIELD OBSERV

Comment (Workings): MINE DEVELED BY 735-FT-DEEP SHAFT WITH LEVELS DRIVEN AT 100-FT INTERVALS. LEVEL 1 HAS 500-FT EAST DRIFT AND 100-FT WEST DRIFT. LEVEL 2 HAS 550-FT EAST DRIFT AND 100-FT WEST DRIFT. LEVEL 3 HAS 600-FT EAST DRIFT. LEVEL 4 NOT OPENED BY EARLIER REPORT CITED 60-FT WEST DRIFT. LEVEL 5 HAS 600-FT EAST DRIFT LEVEL 6 (PRINCIPAL WORKING LEVEL) HAS 200-FT EAST DRIFT WITH STOPES AND 25-FT WINZE SUNK ON SULFIDE LENS. LEVEL 7 HAS 50-FT EAST DRIFT. ABOUT 300 FT WEST OF GOOD HOPE WORKINGS IS 240-FT-DEEP SHAFT (CAVED). SULPHUR SHAFT IS 125 FT DEEP; VULCAN SHAFT IS 410 FT DEEP. PRESENT OPERATION IS ASPHALT-LINED, CYANIDE HEAP-LEACH PAD.

Comment (Deposit): SULFIDE LENS. EPIGENETIC MINERALIZATION PROBANLY CREATED BY SYSTEM OF CONVECTING HOT FLUIDS (ALONG CONTACT BETWEEN SULFIDE LENS AND HOST ROCK) THAT REDISTRIBUTED TRACE ELEMENTS AND PRODUCED ZONES OF INTENSE ALTERATION. DROBECK SHOWED THAT VULCAN DEPOSIT COULD FIT INTO CUPOLA PRE-INTRUSIVE LEVEL OF DEEPER PORPHYRY INTRUSION OF POSSIBLE OLIGOCENE-MIOCENE AGE.

Comment (Deposit): FROM SOURCE AREA; (2) ABSENCE OF WELL-DEFINED FEEDER OR STRATABOUND STRINGER SYSTEM; (3) ZN-RICH NATURE OF LENS. HARTLEY (1983) POSTULATED SECOND, LATER PHASE OF MINERALIZATION IN WHICH AU AND AG IN CHALCEDONIC VEIN SYSTEM SERE RECONCENTRATED FROM PRECIOUS-METAL EXHALITE HORIZON AND INTRODUCED CONTEMPORANEOUSLY WITHIN DEVELOPMENT OF GOSSAN AND S/SE LEN. MINERALIZING SOLUTIONS OF POSSIBLE MIOCENE AGE (SIMILAR IN AGE TO MINERALIZATION IN SAN JUAN MTNS) WOULD HAVE FOLLOWED STRUCTURAL DISCONTINUITY (MASIVE SULFIDE-METAVOLCANIC CONTACT) ALONG WHICH SULFIDES COULD PRECIPITATE TELLURIDES. THIS HOT SPRING STYLE OVERPRINT ON MASIVE SULFIDES MAY HAVE AIDED IN CREATING FAVORABLE GEOCHEMICAL CONDITIONS FOR OXIDATION OF SULFIDE TO NATIVE S. SOURCE OF SE, TE, AU, AG, AND CU IN PRECIOUS-METAL VEIN ZONE IS PROBABLY THE MASSIVE SULFIDE LENS, ALTHOUGH CARBONATITES INTERSECTED IN SUBSURFACE MAY HAVE INTRODUCED THE SE-TE OVERPRINT. DROBECK (1979) PROPOSED PROTEROZOIC STNGENETIC FUMAROLIC ORIGIN OF

Comment (Deposit): COUNTRY ROCK CONSISTS OF FELSIC VOLCANICS (RHYOLITE TUFFS AND RHYOLITIC LAPILLI TUFFS) METAMORPHOSED TO QUARTZOFELDSPATHIC SCHIST. AS RESULT OF HYDROTHERMAL ACTIVITY IN AND NEXT TO MINERALIZED ZONE, SCHISTS HAVE BEEN SERICITIZED, LOCALLY CHLORITIC. FOLIATION IS GENERALLY PARALLEL TO SUBPARALLEL TO BEDDING AND TRENDS EAST-WEST, DIPPING 75 TO 90 NORTH. FELSIC SEQUENCE IS BRACKETED BY THICK BASALTIC ANDESITE FLOWS METAMORPHOSED TO AMPHIBOLITE FACIES. SEQUENCE CONTAINS SEVERAL THIN, DISCONTINUOUS MAGNETITE-BEARING QUARTZITE (METACHERT) BEDS, MOST PROMINENT ONE MILE TO EAST AND APPROXIMATELY ALONG STRIKE OF SULFIDE MINERALIZATION. SEQUENCE IS INTRUDED GENERALLY ALONG FOLIATION BY APOPHYSIS OF TOLVAR PEAK GRANITE AND DISCORDANTLY BY TRACHYTE/TRACHYTE PORPHYRY DIKES. DRILLING NEAR ORE HORIZON INTERSECTED CARBONATITE DIKES (RELATED TO IRON HILL ALKALIC COMPLEX) THAT WERE NOT EXPOSED ON SURFACE. MAGNETIC ANOMALY 0.5 MILE NW OF MINE SUGGESTS POSSIBLE BURIED PYROXENITE PLUG. THREE TYPES OF

Comment (Location): ON DIVIDE BETWEEN CAMP CREEK AND LITTLE CAMP CREEK 0.35 MILE SW OF VULCAN (SITE) AND ABOUT 700 FT WEST OF VULCAN MINE. ; INFO FROM LAND.ST :1976

Comment (Deposit): ADDITIONAL REFERENCES: (11) NARGE, E. M., 1971, GEOLOGIC REPORT--VULCAN DEPOSIT, GUNNISON COUNTY, COLORADO: UNPUB. REPT.; (12) CRAWFORD, E.P., 1927, SELENIUM DEPOSITS AT VULCAN: UNPIB. NOTES; (13) CRAWFORD, W.P., AND JOHNSON, F., 1922, GEOLOGY AND CYANIDATION OF ORE FROM THE GOOD HOPE MINE, VULCAN, COLORADO: COLORADO SCHOOL OF MINES M.SC. THESIS T-477; (14) DROBECK, P.A., 1979, GEOLOGY AND TRACE ELEMENT GEOCHEMISTRY OF A PART OF THE GUNNISON GOLD BELT, COLORADO: COLORADO SCHOOL OF MINES M.SC. THESIS T-2251; (15) LAKES, ARTHUR, 1898, ORES OF THE VULCAN MINE; MINES AND MINERALS, V. 18, P. 562-563; (16) NELSON, A.P., (NO DATE), MINING DISTRICTS, PRODUCING MINES AND PROSPECTIVE PROPERTIES (OF GUNNISON COUNTY): COLORADO STATE LAN. COMM. UNPUB. REPT., P. 5; (17) RICKARD, T.A., 1903, ACROSS THE SAN JUAN MOUNTAINS: ENG. MINING JOUR., V. 76, P. 387; (18) SHARPS, T.I., 1965, SUFUR DEPOSITS OF COLORADO: COLORADO SCHOOL OF MINES MINERAL INDUSTRIES BULL., V. 8, NO. 6; (19) TROST, P.B., 1975,

Comment (Development): SEVERAL CLAIMS, BUT ITS EXPLORATION ACTIVITIES WERE UNKNOWN. IN 1974-1975, NORANDA EXPLORATION OPTIONED AVAILABLE CLAIMS AND CONDUCTED GEOLOGIC MAPPING, VLF-EM AND MAGNETIC SURVEYING, AND DRILLED TWO CORE HOLES. BEGINNING IN 1983, WEBBCO (VULCAN RESOURCES) BEGAN RECOVERY OF AU VIA CYANIDE HEAP-LEACH PAD OPERATION. FAIRLY HOMOGENEOUS DUMP ORE CONSISTING OF VERY FINE-GRAINED AURIFEROUS PYRITE AND CONTAINING ABOUT 0.1 OZ/TON AU IS PELLETIZED, MIXED WITH SLAKED LIME, AND LEACHED ON ASPHALT-LINED PAD, WITH 65 TO 70% RECOVERY.

Comment (Commodity): TETRADYMITE (BI2TE2S) WAS NOT DEFINITELY RECOGNIZED BUT INFERRED ON BASIS OF ANALYSES OF NATIVE TE, RICKARDITE, AND ARSENOPYRITE. VULCAN AND MAMMOTH-GOOD HOPE MINES ARE TYPE LOCALITIES FOR RICKARDITE (CU3TE2) AND WEISSITE (CU5TE3). AURIFEROUS PYRITE AND PETZITE ARE PRINCIPAL AU-BEARING MINERALS. THE NEW TELLURIDE, VULCANITE (CU7TE5), WAS IDENTIFIED ABOUT 1960. GOOD HOPE MINE IS ONLY COLORADO OCCURRENCE OF BERTHIERITE (FESB2S4); SINGLE SPECIMEN NOTED BY RICKARD (1903). ROSCOELITE NOT DEFINITELY IDENTIFIED BUT INFERRED BY RICKARD (1903) ON BASIS OF ASSOCIATION WITH RICKARDITE, WEISSITE, AND NATIVE TE.

Comment (Development): MAMMOTH-GOOD HOPE AND VULCAN MINES ARE PRINCIPAL MINES IN DISTRICT, HAVING PRODUCED FROM 1894 TO 1904 AND INTERMITTENTLY THROUGH 1930 AND MOST RECENTLY BEGINNING IN 1983. INITIAL PROSPECTING WAS IN AU-BEARING GOSSAN OUTCROPS. LENS OF SE-BEARING SULFUR WAS DEVELOPED (PRESUMABLY WITH SMALL PRODUCTION) IN 1907, 1917, AND 1918. A 40-TON-CAPACITY MATTE SMELTER WAS CONSTRUCTED IN 1916 AND TREATED ORE FOR SHORT TIME. FROM 1916 TO 1926, GOOD HOPE MINE WAS OWNED BY GOOD HOPE MINING AND REDUCTION CO., WHOSE PRINCIPAL WAS ONE DR. WEISS (PRESUMABLY FOR WHOM THE TELLURIDE WEISSITE WAS NAMED). VULCAN PROPERTY WAS OWNED BY J.H. HIMEBAUGH. IN 1928, VULCAN, GOOD HOPE, AND OTHER CLAIMS WERE CONSOLIDATED AND OPERATED BY VULCAN CONSOLIDATED MINES CORP, WITH ITS LAST PRODUCTION REPORTED IN 1930. DIAMOND C MINING AND MILLING CO. OF GUNNISON CONTROLLED PROPERTY IN 1937. IN EARLY 1950S, NEWMONT MINING CONDUCTED CU-ZN EXPLORATION BY GEOPHYSICAL SURVEYS AND CORE DRILLING. IN 1962, OSCEOLA MINING CO. STAKED


References

Reference (Deposit): HARTLEY, P.D., 1976, THE GEOLOGY AND MINERALIZATION OF A PRECAMNRIAN MASSIVE SULFIDE DEPOSIT AT VULCAN, GUNNISON COUNTY, COLORADO: STANFORD UNIV. M.SC. THESIS.

Reference (Deposit): HARTLEY, T.D., 1983 GEOLOGY AND MINERALIZATION OF THE VULCAN-GOOD HOPE MASSIVE SULFIDE DEPOSIT, GUNNISON COUNTY, COLORADO, IN HANDFIELD, R.C., ED., GUNNISON GOLD BELT AND POWDERHORN CARBONATITE FIELD TRIP GUIDEBOOK: DREGS, P. 19-27.

Reference (Deposit): HEDLUND, D.C., AND OLSON, J.C., 1975, GEOLOGIC MAP OF THE POWDERHORN QUADRANGLE, GUNNISON AND SAGUACHE COUNTIES, COLORADO: USGS MAP GQ-1178.

Reference (Deposit): LAKES, ARTHUR, 1896, SKETCH OF A PORTION OF THE GUNNISON GOLD BELT, INCLUDING THE VULCAN AND MAMMOTH CHIMNEY MINES: AIME TRANA., V. 26, P. 440-448.

Reference (Deposit): OLSON, J.C. AND OTHERS, 1975, GEOLOGIC MAP OF THE APRING HILL CREEK QUADRANGLE, SAGUACHE COUNTY, COLORADO: USGS MAP MF-713.

Reference (Deposit): SHERIDAN, D.M., AND OTHERS, 1981, PRECABRIAN SULFIDE DEPOSITS IN THE GUNNISON REGION, COLORADO, IN EPIS, R.C., AND CALLENDER, J.F., ED., WESTERN SLOPE COLORADO: NEW MEXICO GEOL. SOC. 32D FIELD CONF. GUIDEBOOK, P 237-277.

Reference (Deposit): CAMERON, E.N., AND THREADGOLD, I.M., 1961, VULCANITE, A NEW COPPER TELLURIDE FROM COLORADO: AM, MINERALOGIST, V. 46, P. 258-268.

Reference (Deposit): COLORADO DIV. MINES INF. REPTS. AND ANNUAL OPERATOR REPTS.

Reference (Deposit): BLM MINERAL SURVEYS MS 10909, 10910, 12454, 12456, 16392, 19920

Reference (Production): COLORADO DIV. MINES ANNUAL OPERATOR REPTS.; USGS MINERAL RESOURCES OF U.S.; HARTLEY, 1983

Reference (Deposit): DROBACK, P.A., 1981, PROTEROZOIC SYNGENETIC MASSIVE SULFIDE DEPOSITS IN THE GUNNISON GOLD BELT, COLORADO, IN EPIS, R.C. AND CALLENDER, J.F., EDS., WESTERN SLOPE COLORADO: NEW MEXICO GEOL. SOC. 32D FIELD CONF. GUIDEBOOK, P. 279-286.


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