Description
John Glasgow (Blackhawk Lode)
Commodities
PrimarySilver, Lead, Zinc
SecondaryCadmium, Gold, Copper, Sulfur-Pyrite
TertiaryBismuth, Tungsten, Beryllium, Manganese
Commodity typeM
Deposit
Model72: Polymetallic replacement
Deposit sizeS
Orebody formTABULAR, LINEAR, IRREGULAR
Ore controlOre Localized (1) In Major Nw-Trending Trunk Fault (Blackhawk) Cutting Any Of 12 Favorable Limestone Beds; (2) Along Parallel Reverse Faults Cutting Limestone In Blackhawk Hanging Wall; (3) Along Zones Of Cross Fractures In Blackhawk Hanging Wall; (4) In Shattered Zones Adjacent To Latite Porphyry Dike; (5) At Intersection Of Two Faults Or Fractures Or Intersection Of Trunk Fault And More Nw-Trending Fault; (6) In Crushed Along Bedding Plane Faults.
Materials
Ore mineralsChalcopyrite, Gold, Hydrozincite, Limonite, Pyrite, Smithsonite, Tennantite
GangueAlabandite, Aurichalcite, Barite, Clinozoisite, Fluorite, Garnet, Helvite, Huebnerite, Kaolinite, Magnetite, Pyrrhotite, Quartz, Rhodochrosite, Topaz
Geology
Host rockShale,Sandstone,Limestone,Latite · Hermosa Formation
Associated rockLatite · Hornblende Latite Porphyry
StructureSan Juan Uplift, Paradox Basin, Rico Dome, Blackhawk Fault, Hidden Fault, Allegheny Fissure, Last Chance Fault, Honduras Fault
Tectonic settingCentral Cordillera (Southern Rocky Mtns)
AlterationAlteration Of Mn-Bearing Carbonates To Mn Oxides; Oxidation Of Sulfide Ores To Carbonates; Oxidation Of Pyrite To Fe Oxides
Economic & production
Development statusPast Producer
First production1879
Last production1976
Discovery year1877
Identification
Deposit ID10101868
MRDS IDD010784
Alternate namesArgentine Mine Encompassing Rico Consolidated, Argentine Shaft, Blackhawk Log Cabin, James G. Blaine Tunnel, Maggie Shaft, Blacksmith Tunnel, And Portion of St. Louis Tunnel
RegionNA
Data scoreA
Coordinates37.70112, -108.00815
References
MCKNIGHT, E.T., 1974, GEOLOGY AND ORE DEPOSITS OF THE RICO DISTRICT, COLORADO: USGS PROF. PAPER 723, P. 81-89.PRATT, W.P., AND OTHERS, 1969, GEOLOGIC MAP OF THE RICO QUADRANGLE, DOLORES AND MONTEZUMA COUNTIES, COLORADO: USGS MAP GQ-797.RANSOME, F.L., 1901, THE ORE DEPOSITS OF THE RICO MOUNTAINS, COLORADO: USGS 22D ANN, REPT., PT. 2, P. 368-372, 374.CROSS, WHITMAN, AND RANSOME, F.L., 1905, DESCRIPTION OF THE RICO QUADRANGLE: USGS FOLIO 130.MUILENBURG, G.A., 1919, MANGANESE DEPOSITS OF COLORADO: CGS BULL. 15, P. 48-49.COLORADO DIV. MINES INF. REPTS. AND ANNUAL OPERATOR REPTS.COLORADO DIV. MINES ANNUAL OPERATOR REPTS.