Mammoth-Revenue Mine

Site Name

Primary: Mammoth-Revenue Mine
Secondary: Mammoth Mine
Secondary: Mammoth Group
Secondary: Patented Claims: Mammoth, MS 5628a
Secondary: Mammoth Mill Site, MS 5628b
Secondary: Middle, MS 5636
Secondary: Revenue, MS 5722
Secondary: Burris, MS 6255
Secondary: Hyman, MS 6255
Secondary: Hallam, MS 6255
Secondary: Grover Cleveland, MS 6256
Secondary: Aztec, MS 6256
Secondary: Morning Star, MS 6256
Secondary: Arms, MS 6256
Secondary: Auraria, MS 6535
Secondary: Etruria, MS 6535
Secondary: Pavonia, MS 6535
Secondary: Servia, MS 6535
Secondary: Umbria, MS 6535

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Commodity

Primary: Gold
Primary: Silver
Secondary: Copper
Secondary: Lead
Tertiary: Molybdenum
Tertiary: Antimony
Tertiary: Zinc

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Location

State: Colorado
County: Conejos
District: Ute (Platoro) 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

Not available

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Workings

Not available

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Ownership

Owner Name: Union Mines
Home Office: Lakewood
Years: 1983 -

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Production

Not available

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Deposit

Record Type: Site
Operation Category: Producer
Deposit Type: Vein
Operation Type: Unknown
Discovery Method: Ore-Mineral In Place
Years of Production:
Organization:
Significant: N
Deposit Size: S

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Physiography

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

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Mineral Deposit Model

Model Name: Epithermal quartz-alunite Au

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Orebody

Not available

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Structure

Type: R
Description: San Juan Volcanic Field

Type: L
Description: Platoro Caldera, Summitville Caldera, Platoro Fault Zone, Cornwall Block

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Alterations

Alteration Type: L
Alteration Text: All Wallrock Is Silicified To Some Extent Within Vein And Up To 6.5 Ft Into Footwall And Up To 16.5 Ft Into Hanging Wall. In Hanging Wall Zones, All Material Within 1.6 Ft Of Vein Is Completely Silicified. Sericite Progressivly Prominent At 1.6 To 6.5 Ft And Dominant From 6.5 To 26 Ft. At 13 Ft, Kaolinite Prominent. At 26 Ft, Rock Shows Regional Argillization.

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Rocks

Name: Quartz Latite
Role: Host
Age Type: Associated Rock Unit
Age in Years: 29.800000+-
Dating Method: K-Ar
Age Young: Oligocene

Name: Quartz Latite
Role: Associated
Age Type: Associated Rock Unit
Age in Years: 29.800000+-
Dating Method: K-Ar
Age Young: Oligocene

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Analytical Data

Analytical Data: HIGH-GRADE ORE, 1.30 OZ/TON AU, 125.50 OZ/TON AG. THREE ORE SHIPMENTS FROM 1889 CONTAINED 15.85 TO 22.36 OZ/TON AU AND 239.70 TO 306.00 OZ/TON AG. TWO ORE SHIPMENTS FROM 1890 CONTAINED 9.73 AND 30.42 OZ/TON AU AND 250.70 AND 402.10 OZ/TON AG.
Analytical Data: MEDIUM-GRADE ORE, 0.88 OZ/TON AU, 8.5 OZ/TON AG
Analytical Data: LOW-GRADE ORE, 0.4 OZ/TON AU, 1.6 OZ/TON AG
Analytical Data: REPRESENTATIVE ORE ASSAYS (PATTON, 1917): MASSIVE ARSENOPYRITE FROM FOOTWALL, 0.4 OZ/TON AU, 1.4 OZ/TON AG

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Materials

Ore: Electrum
Ore: Galena
Ore: Miargyrite
Ore: Digenite
Ore: Silver
Ore: Polybasite
Ore: Molybdenite
Ore: Sphalerite
Ore: Pyrrhotite
Ore: Marcasite
Ore: Zinkenite
Ore: Gold
Ore: Covellite
Ore: Pyrargyrite
Ore: Proustite
Ore: Chalcocite
Gangue: Calcite
Gangue: Barite
Gangue: Chalcedony
Gangue: Quartz
Gangue: Anhydrite

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Comments

Comment (Deposit): FROM 75 NE TO 55 SW. APPARENTLY SOME CYMOID LOOP DEVELOPMENT WITH SPLITTING AND JOINING OF SUBSIDIARY VEINS. MAMMOTH-REVENUE VEIN AND VALLEY QUEEN VEIN (APPARENTLY) FOUND IN FOOTWALL; PAROLE VEIN FOUND IN HANGING WALL. VEIN ZONE COMPOSED OF THREE TYPES OF MATERIAL. FIRST TYPE IS QUARTZ AND SULFIDE ORE IN CENTER OF STRUCTURE. WIDE AREAS ARE HIGHLY BRECCIATED, OFTEN VUGGY WITH WATER-COURSE RESIDUES OF MO AND FE OXIDES. BRECCIATION DECREASED OR ABSENT IN NARROWER PARTS. ORE APPEARS AS RIBBONS OF FINE-GRAINED QUARTZ AND FINE-GRAINED PYRITE/MARCASITE INTERSPERSED WITH WHITE QUARTZ CONTAINING DISSEMINATED PYRITE/MARCASITE AND LATEGANGUE MINERALS. HIGHER GRADE ORE GENERALLY FOUND WHERE SULFIDES CONTAIN RELATIVELY LESS MARCASITE. LOW-MARCASITE HIGH-GRADE ORE SHOWS AG/AU RATIOS OF 50:1 TO 100:1; HIGH-MARCASITE LOWER GRADE ORE SHOWS RATIO OF 10:1. HIGHER METAL VALUES USUALLY FOUND IN CENTER OF HANGING WALL PORTIONS. SECOND TYPE OF MATERIAL IS BROKEN, HIGHLY ALTERED WALLROCK IN SLABS AND BRECCIA

Comment (Deposit): LENSES NEAR FOOTWALL. THIRD TYPE OF MATERIAL IS POST-MINERALIZATION, UNSILICIFIED, INCOMPETENT FAULT GOUGE TOWARD FOOTWALL.

Comment (Workings): MINE DEVELOPED BY MAIN TUNNEL DRIVEN 1600 FT AT S 30 E INTO VEIN, WITH 1200-FT DRIFT ON -100 LEVEL AND 400-FT DRIFT ON -200 LEVEL. BRANCH WORKINGS ON PAROLE VEIN AND SW BRANCH VEIN. RAISE OR WINZE CONNECTS SECOND TUNNEL 253 FT ABOVE MAIN TUNNEL LEVEL. REVENUE TUNNEL IS 332 FT ABOVE TUNNEL LEVEL. DEVELOPMENTS BY CORONADO SILVER IN 1970-72 INCLUDE ADDITIONAL DRIFTS, RAISES, STOPING, AND NEW 450-FT ADIT EAST OF OLD PORTAL.

Comment (Deposit): MAMMOTH-REVENUE IS SOUTHERNMOST OF THREE MINES DEVELOPED ON SOUTH MOUNTAIN-PLATORO FAULT, LARGEST OF SEVERAL QUARTZ-PYRITE VEIN ZONES IN PLATORO FAULT ZONE. FAULT HAS BEEN INTERPRETED AS EXTENDING NW EITHER ON TREND WITH OR JOINING SOUTH MOUNTAIN FAULT OF SUMMIT AND DECATUR WEST DISTRICTS, AND SE INTO BIG LAKE RADIAL FRACTURE SYSTEM. FAULT TRENDS GENERALLY N 30 W WITH 80 TO 90 SW DIP. DUE TO MOVEMENT ON CORNWALL RESURGENT BLOCK IN FOOTWALL, STEEPER PORTIONS OF FAULT CONTAIN WIDER MINERALIZED ZONE THAN LESS STEEPLY DIPPING PORTIONS. DISPLACEMENT DECREASES SE FROM STUNNER PASS TO FOREST KING MTN-MAMMOTH MTN SADDLE. NORTH PART OF VEIN ZONE EXCEEDS 150 FT IN THICKNESS BUT DECREASES TO 50 FT SOUTH OF INTERSECTION WITH ENE-TRENDING EMMA CROSS-FAULT. IN MAMMOTH-REVENUE MINE, VEIN IS ACTUALLY VEIN ZONE CONSISTING OF NETWORK OF INTERWOVEN VEINS GENERALLY PARALLELING MAJOR FAULT BUT WITH CONSIDERABLE VARIATIONS, FROM N 0 TO 25 W IN STRIKE AND 85 NE TO 70 SW IN DIP. LESSER VEINS DIP VARIABLY

Comment (Commodity): ARSENOPYRITE REPORTED BY PATTON (1917) CITED FOR ENTIRE DISTRICT. PETZITE (TELLURIDE) REPORTED BY PATTON IN GILMORE AND PLATORO DISTRICTS WAS PROBABLY MISIDENTIFIED SULFIDE (BIRD, 1973). MINOR PRODUCTION OF CU AND PB UNCERTAIN DUE TO LACK OF OLDER PRODUCTION RECORDS.

Comment (Location): CLAIMS LIE ALONG NE BASE OF FOREST KING MTN SOUTH OF CONEJOS RIVER ON SW SIDE OF TOWN. ELEV AND LAT-LONG GIVEN ARE FOR TUNNEL PORTAL IN NW SW NE SEC. 22 (SECTIONS PROJECTED INTO UNSURVEYED AREA). ; INFO FROM LAND.ST :1975

Comment (Production): PARTIAL PRODUCTION RECORD. ANNUAL PRODUCTION AND CUMULATIVE PRODUCTION FOR 1889-1906 NOT AVAILABLE. PRODUCTION IS CITED FOR 1966 IN USBM MINERALS YEARBOOK, BUT FIGURES ARE WITHHELD. AU AND AG VALUES FOR 1969 ARE CALCULATED FROM REPORTED ORE TONNAGE AND MEDIAN OF CALCULATED ORE GRADES USING 1968 AND 1970 FIGURES. OTHER ESTIMATED AU AND AG VALUES HAVE BEEN ROUNDED TO NEAREST OZ FROM REPORTED FRACTIONAL VALUES. CUMULATIVE AU AND AG VALUES HAVE BEEN ROUNDED AFTER TOTALLING OF FRACTIONAL REPORTED VALUES. FIGURES FOR 1974 INCLUDE BOTH MINED ORE AND MILLED ORE FROM STOCKPILE AT MILL.

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References

Reference (Deposit): BIRD, W.H., 1973, DEVELOPMENT OF THE SOUTHERN PORTION OF THE PLATORO CALDERA COMPLEX AND ITS RELATED MINERAL DEPOSITS, SOUTHEAST SAN JUAN MOUNTAINS, COLORADO: COLORADO SCHOOL OF MINES THESIS T-1440.

Reference (Deposit): PATTON, H.B., 1917, GEOLOGY AND ORE DEPOSITS OF THE PLATORO-SUMMITVILLE MINING DISTRICT, COLORADO: CGS BULL. 13.

Reference (Production): COLORADO DIV. MINES ANN. OPERATOR REPTS.; USBM MINERALS YEARBOOKS 1966-1974

Reference (Deposit): LIPMAN, P.W., 1974, GEOLOGIC MAP OF THE PLATORO CALDERA AREA, SOUTHEASTERN SAN JUAN MOUNTAINS, SOUTHWESTERN COLORADO: USGS MAP I-828.

Reference (Deposit): BIRD, W.H., 1972, MINERAL DEPOSITS OF THE SOUTHERN PORTION OF THE PLATORO CALDERA COMPLEX, SOUTHEAST SAN JUAN MOUNTAINS, COLORADO: MTN. GEOLOGIST, V. 9, NO. 4, P. 379-387.

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

Reference (Deposit): BLM MINERAL SURVEYS MS 5628A&B, 5722A&B, 5636A&B, 6255, 6256, 6535

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