| Location: | La Plata, Montezuma County, Colorado, United States, North America |
| Lat / long: | 37.39941, -108.06425 |
| dep_id: | 60000378 |
| mrds_id: | D010861 |
| Commodity type: | metallic |
| Major mineral: | Copper, Lead, Silver, Gold |
| Minor mineral: | Mercury, Vanadium, Uranium, Zinc |
| Trace mineral: | Tellurium, PGE, Iron |
| Operation type: | Unknown |
| Deposit type: | VEIN, DISSEMINATION, REPLACEMENT, CONTACT METAMORPHIC, PLACER, WEATHERING RESIDUAL (BOG) |
| Production size: | Small ammount of material produced |
| Development status: | Producer |
| alteration: | ALTERATION OF IGNEOUS ROCKS: (A) SERICITIZATION AND KAOLINITIZATION OF FELDSPAR IN PORPHYRY., ALTERATION OF IGNEOUS ROCKS:(A) SERICITIZATION AND KAOLINITIZATION OF FELDSPAR IN PORPHYRY, ALTERATION OF IGNEOUS ROCKS: (B) CHLORITIZATION OF FERROMAGNESIAN MINERALS., ALTERATION OF IGNEOUS ROCKS: (C) LIMONITIZATION OF FERROMAGNESIAN MINERALS., ALTERATION OF IGNEOUS ROCKS: (D) SILIFICATION OF PORPHYRY AND SEDIMENTARY WALL ROCK NEAR ORE VEINS. OXIDATION OF AURIFEROUPYRITE AND CU SULFIDES. CONTACT METAMORPHISM NEAR NONPORPHYRITIC INTRUSIVES: (A) SILIFICATION OF SANDSTONES, (B) HORNFELSIZATION OF SHALE AND MUSTONE, (C) CALCITIZATION IN LIMESTONE AND LIMY NODULES, (D) GRAPHITIZATION OF CARBONACEOUS BEDS IN CRETACEOUS FORMATIONS., ALTERATION OF IGNEOUS ROCKS: (D) OXIDATION OF AURIFEROUPYRITE AND CU SULFIDES. CONTACT METAMORPHISM NEAR NONPORPHYRITIC INTRUSIVES: (A) SILIFICATION OF SANDSTONES, (B) HORNFELSIZATION OF SHALE AND MUSTONE, (C) CALCITIZATION IN LIMESTONE AND LIMY NODULES, (D) GRAPHITIZATION OF CARBONACEOUS BEDS IN CRETACEOUS FORMATIONS. |
| conc_proc: | ENRICHMENT OF NATIVE AU BY NEAR-SURFACE WEATHERING OF TELLURIDES AND AURIFEROUS PYRITE |
| ore_ctrl: | STRUCTURAL CONTROL: NORMAL FAULTS AND FRACTURES LOCALIZED ORE AT CHANGES IN STRIKE, SPLITS AND REUNIONS, SEGMENTS OF STEEP DIP, SEGMENTS OF REVERSED DIP, AND INTERSECTIONS OF ORE-BEARING VEINS WITH OTHER FRACTURES, BRECCIA ZONES, AND STRONG BARREN FAULTS. ROCK CHARACTER CONTROL: LIMESTONE FAVORABLE TO CHEMICAL REPLACEMENT BY ORE SOLUTIONS, BRECCIATION OF SILICIFIED BRITTLE CONGLOMERATE, SANDSTONE, LIMESTONE, AND SILICIFIED OR UNSILICIFIED PORPHYRY. GEOMORPHIC CONTROL: PLACER AU LOCALIZED IN STREAM VALLEYS BELOW ERODED AND GLACIATED MINERALIZED AREAS. OTHER CONTROL: INORGANIC PRECIPITATION OF FE OXIDE AND NATIVE CU BY GROUND WATER IN POST-GLACIAL, NEAR-SOURCE, SWAMP/BOG ENVIRONMENT. |
| Structure: | LA PLATA DOME, MAYDAY-IDAHO FAULT SYSTEM, PARROTT FAULT SYSTEM, SAN JUAN UPLIFT, FOUR CORNERS PLATFORM |
| Year first produced: | 1873 |
| yr_lst_prd: | 1980 |
| dy_ba: | > |
| disc_yr: | 1700 |
| References: |
- Deposit:: ECKEL, E.B., AND OTHERS, 1949, GEOLOGY AND ORE DEPOSITS OF THE LA PLATA DISTRICT, COLORADO: USGS PROF. PAPER 219.
- Deposit:: CROSS, WHITMAN, AND OTHERS, 1899, DESCRIPTION OF THE LA PLATA QUADRANGLE: USGS FOLIO 60.
- Deposit:: ECKEL, E.B., 1938, COPPER ORES OF THE LA PLATA DISTRICT, COLORADO, AND THEIR PLATINUM CONTENT: COLORADO SCI. SOC. PROC., V. 12, NO. 12, P. 647-664.
- Deposit:: PARKER, B.H., JR., 1974, GOLD PLACERS OF COLORADO: COLORADO SCHOOL OF MINES QUART., V. 69, NO. 4, P. 194-197.
- Deposit:: HENDERSON,C.W., 1926, MINING IN COLORADO, A HISTORY OF DISCOVERY, DEVELOPMENT, AND PRODUCTION: USGS PROF. PAPER 138, P. 52, 177-178.
- Deposit:: NELSON-MOORE, J.L., AND OTHERS, 1978, RADIOACTIVE MINERAL OCCURRENCES OF COLORADO AND BIBLIOGRAPHY: CGS BULL. 40, P. 204-206.
- Deposit:: HARRER, C.M., AND TESCH, W.J., JR., 1959, RECONNAISSANCE OF IRON OCCURRENCES IN COLORADO: USBM IC-7918, P. 48, 51-52.
- Deposit:: COLORADO DIV. MINES ONF. REPTS. AND ANNUAL OPERATOR REPTS.
- Deposit:: UNPUBLISHED ENGINEERING REPTS. 1904-1936 (SEE INDIVIDUAL MINE RECORDS FOR SPECIFIC REFERENCES)
- Deposit:: BLM MINERAL SURVEYS MS 1097.5
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