Enterprise Mine

Site Name

Primary: Enterprise Mine
Secondary: Patented Claims: Snowflake, MS 5909
Secondary: Sun Up, MS 5910
Secondary: Bell, MS 5911, Enterprise, MS 5916
Secondary: Kitchen, MS 5917
Secondary: Ontario, MS 5923
Secondary: Eureka, MS 6285
Secondary: Song Bird, MS 6392
Secondary: Thompson, MS 6394
Secondary: Hiawatha, MS 6399

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Commodity

Primary: Silver
Primary: Lead
Primary: Zinc
Secondary: Copper
Secondary: Gold
Tertiary: Manganese

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Location

State: Colorado
County: Dolores
District: Pioneer (Rico) District

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Land Status

Land ownership: National Forest
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.
Administrative Organization: San Juan N. F.

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Holdings

Not available

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Workings

Not available

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Ownership

Owner Name: Rico-Argentine Mining Co.
Home Office: Salt Lake City, Ut.
Years: 1948 -

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Production

Year: 1929
Material type: ORE AG PB ACC
Description: Ap_Grade: ^77.937 Oz/Ton Ag, 10.267% Pb, 14.394% Zn, 1.414% Cu, 0.7005 Oz/Ton Au

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Deposit

Record Type: Site
Operation Category: Past Producer
Operation Type: Unknown
Year First Production: 1887
Year Last Production: 1929
Discovery Year: 1887
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: Polymetallic replacement

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Orebody

Form: TABULAR

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Structure

Type: R
Description: San Juan Uplift, Paradox Basin

Type: L
Description: Rico Dome

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Alterations

Alteration Type: L
Alteration Text: Silicification Of Sandstone To Orthoquartzite Near Porphyry Contact; Marbleization Of Limestone Near Porphyry Contacts; Silicification Of Blanket Breccia And Shale

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Rocks

Name: Latite
Role: Associated
Age Type: Host Rock Unit
Age Young: Pennsylvanian

Name: Latite
Role: Associated
Age Type: Host Rock
Age Young: Pennsylvanian

Name: Latite
Role: Associated
Age Type: Associated Rock
Age Young: Paleocene

Name: Latite
Role: Associated
Age Type: Associated Rock Unit
Age Young: Paleocene

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Analytical Data

Analytical Data: SWICKHIMER'S ORE DISCOVERY IN ENTERPRISE SHAFT ASSAYED 519.4 OZ/TON AG AND 2.1 OZ/TON AU
Analytical Data: ORE DELIVERED TO MILL ASSAYED 10.03OZ/TON AG, 7.175% PB, 8.408% ZN, 0.866% CU, 0.0515 OZ/TON AU. RICKARD GIVES COMPOSITION OF FIRST-CLASS ORE AS 221.5 OZ/TON AG, 10.2% PB, 12.0 0% ZN, 0.87 OZ/TON AU, 11.8% FE, 11.6% S, 2.0% MN, 29.2% SIO2
Analytical Data: ENTERPRISE VEIN DISCOVERY ASSAYED 285.5 OZ/TON AG AND 3.2 OZ/TON AU. RANSOME (1901) GIVES RANGE OF ENTERPRISE ORE AS 100 TO 200 OZ/TON AG, 0 TO 10% PB, 0 TO 15% ZN, 0.5 TO 3 OZ/TON AU. ORE DELIVERED TO SMELTER IN 1929 ASSAYED 77.937 OZ/TON AG, 10.267% PB, 14.394% ZN, 1.414% CU, 0.7005 OZ/TON AU
Analytical Data: SECOND-CLASS ORE CONTAINED 45 TO 75 OZ/TON AG, 2 TO 3% PB, 5 TO 7% ZN, 6 TO 10%FE, 5 TO 8% S, 6 TO 10% MN, 50 TO 55% SIO2.

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Materials

Ore: Proustite
Ore: Malachite
Ore: Gold
Ore: Covellite
Ore: Chalcopyrite
Ore: Stephanite
Ore: Argentite
Ore: Polybasite
Ore: Sphalerite
Gangue: Quartz
Gangue: Rhodochrosite
Gangue: Siderite
Gangue: Rhodonite
Gangue: Calcite

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Comments

Comment (Location): (LAND STATUS AND ADMINISTRATIVE AREA LOCATIONS CALCULATED USING GIS OVERLAY ANALYSIS FOR SAN JUAN N. F.). MINE LIES ON WEST SLOPE OF NEWMAN HILL AND ADJOINS NEWMAN AND RICO-ASPEN WORKINGS (UNSURVEYED SECTION). CLAIMS LISTED ARE SWICKHIMER'S ORIGINAL CLAIMS; SOME MAY LATER HAVE BEEN CONSOLIDATED INTO ENTERPRISE OR INTO PRO PATRIA PROPERTY. ELEV AND LAT-LONG GIVEN ARE FOR ENTERPRISE SHAFT AND ARE FROM MCKNIGHT, 1974, PL. 1 (1930 BASE). ; INFO FROM LAND.ST :1975

Comment (Production): PARTIAL PRODUCTION RECORD. FIGURES UNAVAILABLE FOR YEARS PRIOR TO AND AFTER 1929. FIRST GRADE IS THAT FOR ORE SHIPPED TO SMELTER; SECOND IS ORE SHIPPED TO MILL.

Comment (Deposit): FILLING AND PARTLY AS METASOMATIC REPLACEMENT OF BRECCIA MATERIAL. LITTLE ORE FOUND IN BLANKET NE OF LAURA SHAFT. BLANKETS ARE TABULAR AND LINEAR FEATURES FORMING RHOMBOID PLAN AND LOCALIZED OVER NE AND NW FISSURE VEINS. PECULIAR ASPECT IS THAT BOTH SETS OF VEINS SPLIT INTO QUARTZ STRINGERS AND VEINLETS AND BECOME IMPOVERISHED ON APPROACH TO CONTACT LIMESTONE, USUALLY WITHIN 20 TO 30 FT AND ESPECIALLY IN ZONE OF THINBEDDED SANDSTONES AND SHALES BENEATH CONTACT LIMESTONE. BLANKET ORES PROVED LARGER AND RICHER ABOVE NW CROSS VEINS THAN OVER NE PAY VEINS, BUT NOT ALL NW CROSS VEINS TOPPED BY BLANKET ORE. NO VEIN ORE FOUND ABOVE BLANKET, BUT SOME EVIDENCE OF DISRUPTION AND FLEXURE NOTED IN SHALES ABOVE FISSURES.

Comment (Development): AND WAS FIRST EVIDENCE OF FLAT BLANKET ORES. AFTER ADDITIONAL DEVELOPMENTS, ENTERPRISE VEIN DISCOVERED, AND BY 1890, SEVERAL CLAIMS HAD BEEN CONSOLIDATED INTO ENTERPRISE MINING CO. ENTERPRISE DISCOVERIES LED TO BOOM IN DISTRICT FROM 1887-1892. LATER HISTORY OF MINE NOT KNOWN, BUT IT DID PRODUCE ORE AT LEAST AS 1929 UNDER PELLEYRE MINING AND MILLING CO.

Comment (Deposit): LOWER HERMOSA FM SANDSTONE, SHALE, AND LIMESTONE TREND GENERALLY N 60 TO 75 E, DIP 10 TO 15 SE. PRINCIPAL NE-TRENDING, SMALL-DISPLACEMENT, NEAR-VERTICAL FISSURE VEINS INCLUDE (FROM NW TO SE) SWANSEA (N 48 E), KITCHEN (N 53 E), ENTERPRISE (N 50 E), SONGBIRD (N 47 E), HIAWATHA (N 40 E), EUREKA (N62 E), JUMBO NO. 2 (N 34 E), AND JUMBO NO. 3 (N 32 E). VEINS CHARACTERIZED BY WELL FORMED BANDS OF QUARTZ AND RHODOCHROSITE OFTEN RIMMING LIMESTONE AND SANDSTONE INCLUSIONS, STREAKS OF GALENA AND SPHALERITE, THIN DISCONTINUOUS CLAY SELVAGES, AND CASINGS OF SANDSTONE AND CRUSHED ROCK. ALTHOUGH EVIDENCE SUGGESTS ALL BANDING WAS DEPOSITIONAL, JUMBO 3 SHOWS POST-ORE REOPENING AND REDEPOSITON. ALSO SLIGHT OFFSETS OF FAULT ALONG BEDDING PLANE SLIPS. VEINS FLATTEN SLIGHTLY WHEN TRAVERSING LIMESTONE; IN SANDSTONE, VEINS STRAIGHTEN AND SHOW ENRICHMENT INORE. UNLIKE WALLS APPEAR BEST ENVIRONMENT FOR RICHER ORES, BEST WHERE FOOTWALL IS SANDSTONE AND HANGING WALL IS LIMESTONE. SELVAGES MOST NOTICEABLE IN

Comment (Deposit): LIMESTONE, INFREQUENT IN SANDSTONE. LARGER-DISPLACEMENT CROSS VEINS TREND FROM NEARLY NORTH-SOUTH TO ABOUT N 45 W AND DIP AS SHALLOW AS 40 NE OR SW. SOME DISPLACE NE PAY VEINS WHILE OTHERS DO NOT. VEINS CONTAIN CRUSHED ROCK, QUARTZ GOUGE, SOME PYRITE, AND SOME AU AND AG. RICKARD BELIEVED BETTER ORE IN CROSS VEINS RESULTED FROM DRAG THROUGH OFFSET ACROSS NE PAY VEINS. RICHEST ORES FOUND IN BLANKET REPLACEMENTS ABOVE CONTACT LIMESTONE. BED IS AVERAGE 6-FT-THICK BRECCIATED SHALE OCCASIONALLY CONTAINING SANDSTONE FRAGMENTS FROM OVERLYING BEDS. RICKARD DESCRIBED CONTACT ORE AS OCCURRING (1) CRYSTALLINE LIMESTONE OVERLAIN BY BLACK SHALE AND UNDERLAIN BY SANDSTONE, (2) LIMESTONE BRECCIA OVERLAIN BY ANDSTONE AND UNDERLAIN BY GRAY LIMESTONE, (3) CRUSHED LIMESTONE OVERLAIN BY BLACK SHALE AND UNDERLAIN BY BLOCKY LIMESTONE. IN PLACES SUCH AS IN JUMBO VEIN, HORIZON IS OCCUPIED BY GYPSUM LAYER SHOWING IRREGULAR SOLUTION FEATURES. BLANKET ORE BELIEVED TO HAVE BEEN DEPOSITED PARTLY AS INTERSTITIAL

Comment (Development): FOLLOWING HARRY IRVING'S ORE DISCOVERY ON NEWMAN HILL IN 1879, WORK BEGAN ON SWANSEA, SONGBIRD, AND ENTERPRISE CLAIMS. SWANSEA EXHAUSTED BY 1883. BECAUSE NATURE OF FAULTING WAS NOT YET KNOWN, MINERS THOUGHT VEINS TO BE DISCONTINUOUS; NEWMAN HILL DISCOVERIES WERE DISCREDITED AND CLAIMS ABANDONED. IN 1884, LARNED AND HACKETT WORKED SWANSEA LEVEL, DISCOVERED VEIN TO BE FAULTED, AND PRODUCED ORE. IN 1886, A.A. WAGGENER AND GEROGE BARLOW RELOCATED SONGBIRD CLAIM, BUT FLOODING AND LACK OF CAPITAL HINDERED DEVELOPMENT. AT END OF 1886, DAVID SWICKHIMER BOUGHT THEIR INTERESTS & FROM HIS EXPERIENCE IN SWANSEA MINE, RECOMMENDED SINKING ENTERPRISE SHAFT. MEANWHILE IN 1887, LARNED AND HACKETT DROVE NORTHWARD TOWARD SWANSEA CLAIM BOUNDARY; SWICKHIMER HAD TO FIND ORE OR HIS CLAIM COULD BE DISPUTED. ON VERGE OF NOT KEEPING UP ASSESSMENTS, LOSING LOCAL CREDIT AND NOW UNPAID MINERS, SWICKHIMER'S WIFE WON LOUISIANA LOTTERY, WHICH PAID DEBTS AND BOUGHT SUPPLIES. ON 10/6/87, HE HIT ORE AT 262 FT IN SHAFT

Comment (Workings): MINE DEVELOPED BY ENTERPRISE, JUMBO, AND LAURA SHAFTS AND BY GROUP TUNNEL. LOWEST LEVEL IS GROUP TUNNEL (ELEV 9247), LOCATED 1000 FT NW OF SHAFT, DRIVEN S 57 E ABOUT 3000 FT. JUMBO SHAFT (ELEV 9706) LOCATED 650 FT SSW OF ENTERPRISE SHAFT AND SUNK ABOUT 880 FT. LAURA SHAFT (ELEV 9910) LOCATED 1300 FT NE OF ENTERPRISE SHAFT AND SUNK ABOUT 610 FT. DRIFTS DRIVEN FROM GROUP TUNNEL ON SWANSEA, ENTERPRISE, EUREKA, AND JUMBO 2 AND 3 VEINS. ABOVE GROUP TUNNEL IS 100 (MAIN) LEVEL FROM WHICH NUMEROUS RAISES EXTEND TO COMPLEX, INTERCONNECTING DRIFTS AND STOPES IN BLANKET AT VARIABLE HEIGHT ABOVE 100 LEVEL. ON JUMBO NO. 3 VEIN, 150-FT INTERMEDIATE LEVEL DEVELOPED BETWEEN GROUP TUNNEL AND LAURA CROSSCUT. ON ENTERPRISE VEIN AT LAURA SHAFT, INTERMEDIATE LEVEL LIES 125 FT ABOVE 100 LEVEL, AND LAURA LEVEL LIES ABOUT 220 FT ABOVE 100 LEVEL. BLANKET DRIFT LEVEL CUTS ACROSS BOTH HIGHER LEVELS.

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References

Reference (Deposit): MCKNIGHT, E.T., 1974, GEOLOGY AND ORE DEPOSITS OF THE RICO DISTRICT, COLORADO: USGS PROF. PAPER 723, P. 73-75.

Reference (Deposit): PRATT, W.P., AND OTHERS, 1969, GEOLOGIC MAP OF THE RICO QUADRANGLE, DOLORES AND MONTEZUMA COUNTIES, COLORADO: USGS

Reference (Deposit): RANSOME, F.L., 1901, THE ORE DEPOSITS OF THE RICO MOUNTAINS, COLORADO: USGS 22D ANN. REPT., PT. 2, P. 308-328.

Reference (Deposit): CROSS, WHITMAN, AND RANSOME, F.L., 1905, DESCRIPTION OF THE RICO QUADRANGLE: USGS FOLIO 130.

Reference (Deposit): RICKARD, T.A., 1895, VEIN STRUCTURE IN THE ENTERPRISE MINE: COLORADO SCI. SOC. PROC., V. 5, P. 123-130

Reference (Deposit): RICKARD, T.A., 1896, THE ENTERPRISE MINE, RICO, COLORADO: AIME TRANS., V. 26, P. 906-980.

Reference (Deposit): FARISH, J.B., 1892, ON THE ORE-DEPOSITS OF NEWMAN HILL, NEAR RICO, COLORADO: COLORADO SCI. SOC. PROC., V. 4, P. 151-164.

Reference (Deposit): BASTIN, E.S., 1922, SILVER ENRICHMENT IN THE SAN JUAN MOUNTAINS, COLORADO: USGS BULL. 735-D, P. 115

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

Reference (Deposit): BLM MINERAL SURVEYS MS 5909, 5910, 5911, 5916, 5917, 5923, 6285, 6392, 6394, 6399

Reference (Production): COLORADO DIV. MINES ANNUAL OPERATOR REPTS. (SHAMROCK, ATLANTIC CABLE, AND ENTERPRISE MINES

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