NBMG Sample Location 1441, Comet Mining District, Lincoln County, Nevada, USAi

Regional Level Types
NBMG Sample Location 1441	Occurrence
Comet Mining District	Mining District
Lincoln County	County
Nevada	State
USA	Country

Structure: Fractures

Alteration: Silicification

Deposit: Short adit follows an oxidized sulfide replacement vein in thick-bedded (1-ft beds) to massive limestone beds. Upper adit is in bold carbonate, outcrop. At lower adit, the host limestone is a medium grey sugary slightly dolomitic (silicified?) limestone containing algal structures and fossil fragments. Near vein, fossil remnants are replaced by calcite or iron oxides. Vein is well-exposed at lower and upper portals. The "vein" or altered fracture (fissure) zone is about 3-5 ft wide, striking N 70 W at lower working to e- W at upper working. Altered limestone within zone is silicified and contains abundant Fe and Mn oxides. Replacement appears to have taken place along several vertical fractures or fissures at a high angle to the bedding. The altered rock within the zone shows gossany honeycomb boxworks and irregular pods and veins of coarse calcite/siderite, quartz and manganosiderite. Sample 1441 was collected from outcrop at portal and consists of replacement ore with irregular clots of galena, sphalerite, specularite, oxidized pyrite, and abundant Fe and Mn oxides within a manganosiderite-calcite-quartz gangue. Rocks are heavy and silicified, and euhedral crystalline quartz li

Deposit type: Polymetallic replacement

Development: Recent (within year prior to aug 1983) scraping and trenching with bulldozer. Road to cabin is extensively bulldozed. Dozing may be in preparation for drilling; upper roads not visited; possibly drill sites.

Rock formation(s): Lyndon Limestone;Pioche Shale, Highland Peak


Ore(s): Vertical Fractures Or Fissures At A High Angle To Bedding

References

Other Databases

Link to USGS MRDS:	10097291

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