Lone Cone District

Dolores County, Colorado, United States

SilverGoldCopperLeadCoalAntimonyManganeseSulfurTelluriumZinc

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Description

John A Gilmore

Commodities

PrimarySilver, Gold, Copper, Lead

SecondaryCoal

TertiaryAntimony, Manganese, Sulfur, Tellurium, Zinc

Commodity typeB

Deposit

Model85: Polymetallic veins

Deposit sizeS

Ore controlPrincipal Fissures Of Graben System

Materials

Ore mineralsArgentite, Chalcocite, Chalcopyrite, Coal, Galena, Polybasite, Pyrargyrite, Pyrite, Sphalerite, Stibnite, Tennantite

GangueBarite, Chalcedony, Epsomite, Gypsum, Melanterite, Quartz, Rhodochrosite, Sulfur

Geology

Host rockShale,Siltstone,Sandstone · Dolores Formation;Cutler Formation

Associated rockGabbro,Latite,Basalt · Microgabbro;Calico Peak Porphyry

StructureSan Juan Uplift, Paradox Basin, Rico Dome, Dunton Syncline, Calico Peak Anticline, Dunton Fault, Papoose Fault, Emma Fault, Almont Fault, Unnamed Faults

Tectonic settingCentral Cordillera (Southern Rocky Mtns)

AlterationSilicification Of Sandstone Wall Rocks Near Fissures; Some Oxidayion Of Sulfide Ores

Economic & production

Development statusProducer

First production1885

Last production1980

Discovery year1880

Identification

Deposit ID10087921

MRDS IDD010908

Alternate namesGold Nugget Mill Site, MS 16240b, Dunton District, Patented Claims: Little Wounder, MS 1516, Great Bear, MS 12930, Lion, MS 12930, Sirius, MS 12931, Little Emma, MS 12951a, Dunton Mill Site, MS 12951b, Orion, MS 12953a, Orion Mill Site, MS 12953b, Otsego Estension, MS 15746a, Otsego Mill Site, MS 15746b, Otsego, MS 15747a, Otsego Extension Mill Site, MS 15747b, Gold Nugget, MS 16240a, Como, MS 16246a, Como Mill Site, MS 16246b, Horlick, MS 17235a, Almont, MS 17235a, Yule, MS 17235a, Priest, MS 17235a, Heddle, MS 17235a, Smuggler, MS 17235a, Lombard, MS 17235a, Dick, MS 17235a, Mount Pleasant Mill Site, MS 20539, Lombard Mill Site, MS 17235b, Columbia, MS 18486a, America, MS 18486a, Nil Desperandum, MS 18486a, Brooklyn MS 18498, Mayflower, Ms18499, Susie, MS 18519, Nettie, MS 18519, Little May, MS 18519

RegionNA

Data scoreA

Coordinates37.77279, -108.09482

References

BUSH, A.L., AND BROMFIELD, C.S., 1966, GEOLOGIC MAP OF THE DOLORES PEAK QUADRANGLE, DOLORES AND SAN MIGUEL COUNTIES, COLORADO: USGS MAP GQ-536.PRATT, W.P., AND OTHERS, 1969, GEOLOGIC MAP OF THE RICO QUADRNAGLE, DOLORES AND NONTEZUMA COUNTIES, COLORADO: USGS MAP GQ-797.BASTIN,E.S., 1922, SILVER ENRICHMENT IN THE SAN JUAN MOUNTAINS, COLORADO: USGS BULL. 735-D, P. 116-129.KRANTZ, P.R., AND FREEMAN, W.H., 1923, A STUDY OF THE ORES OF DUNTON DOLORES COUNTY, COLORADO: COLORADO SCHOOL OF MINES THESIS T-503.HENDERSON, C.W., 1926, MINING IN COLORADO, A HISTORY OF DISCOVERY, DEVELOPMENT, AND PRODUCTION: USGS PROF. PAPER 138, P. 114-117.COLORADO DIV. MINES INF. REPTS. AND ANNUAL OPERATOR REPTS.BLM MINERAL SURVEYSMCKNIGHT, E.T., 1974, GEOLOGY AND ORE DEPOSITS OF THE RICO DISTRICT, COLORADO: USGS PROF. PAPER 723.HENDERSON, 1926, P. 117; MCKNIGHT, 1974, P. 6; USGS/USBM MINERAL RESOURCES OF U.S.; USBM MINERAL YEARBOOKS; COLO. DIV. MINES ANN. OPERATOR REPTS.