Como Gold-Silver Property

Past Producer in Lyon county in Nevada, United States with commodities Gold, Silver, Copper, Lead, Zinc

Sections on this page

Identification information
Geographic coordinates
Site location context
Geographic areas
Public Land Survey System information
Commodities
Materials information
Alteration
Mineral occurrence model information
Host and associated rocks
Nearby scientific data
Geologic structures
Ore body information
Controls for ore emplacement
Economic information about the deposit and operations
Mining district
Land status
Ownership information
Bibliographic references
General comments
Reporter information

Geologic information

Identification information

Deposit ID	10310425
Record type	Site
Current site name	Como Gold-Silver Property
Alternate or previous names	Boyle, Pony Meadows, Hulley-Logan Mine Areas
Related records	10043884

Comments on the site identification

This record is for the currently explored Como gold-silver property which encompasses the main central area of the Como District which had historic production and whose mines are described by earlier individual MRDS records.

Geographic coordinates

Geographic coordinates:	-119.47932, 39.15268 (WGS84)
Relative position	The Como gold-silver property is located about 30 miles southeast of Reno and 15 miles east of Carson City.

Site location context

Political divisions (FIPS codes)

Lyon(county)

Nevada(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Como(quadrangle 1:24,000 scale)

Carson City(quadrangle 1:100,000 scale)

Reno(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Middle Carson(hydrologic unit)

Carson(hydrologic accounting unit)

Central Lahontan(hydrologic subregion)

Great Basin(hydrologic region)

Federal lands

Bureau of Land Management(Bureau of Land Management NV)

Bureau of Land Management NV BLM(Type of land area)

BLM(Federal land areas administered by BLM)

Geographic areas

Country	State	County
United States	Nevada	Lyon

Public Land Survey System information

Meridian	Township	Range	Section	Fraction	State
Mount Diablo	015N	022E	01 02 11 12 13 14 15		Nevada
Mount Diablo	015N	023E	06 07 18		Nevada

Comments on the location information

The Como gold-silver property is located in the area of the main Como District mines on the north slope of the Pine Nut Mountains. It consists of 5 patented claims and 60 unpatented mining claims.

Commodities

Commodity	Importance
Gold	Primary
Silver	Primary
Copper	Tertiary
Lead	Tertiary
Zinc Critical	Tertiary

Comments on the commodity information

Commodity Info: silver/gold ratio of 25/1
Ore Materials: free gold, pyrite, silver chloride,tetrahedrite, copper-lead-zinc minerals
Gangue Materials: quartz, pyrite, sericite, clay minerals, alunite

Materials information

Materials	Type of material
Gold	Ore
Pyrite	Ore
Chlorargyrite	Ore
Tetrahedrite	Ore
Quartz	Gangue
Pyrite	Gangue
Sericite	Gangue
Clay	Gangue
Alunite	Gangue

Alteration

(Local) Vikre and McKee have identified five distinct hydrothermal mineral alteration assemblages affecting the host andesite in the Como District. Some of these are spatially restricted to vein selvages and others are more widespread. Mixed clay alteration assemblages indicate periodic changes from acid leaching to neutral conditions during gold-silver deposition. Alteration minerals proesent are: quartz, diaspore, sericite, kaolinite,dickite, halloysite, pyrophyllite, pyrite, montmorillonite, and alunite.

Mineral occurrence model information

Model code	150
USGS model code	25c
Deposit model name	Epithermal vein, Comstock
Mark3 model number	16

Host and associated rocks

Host or associated

Host

Rock type

Volcanic Rock (Aphanitic) > Intermediate Volcanic Rock > Andesite

Stratigraphic age (youngest)	Late Miocene
Chronological age	7.5
Dating method	K-Ar
Stratigraphic age (youngest)	Late Miocene
Chronological age	6
Dating method	K-Ar

Nearby scientific data

(1)	-119.47932, 39.15268	ListMap

Economic information

Geologic structures

Type of structure	Regional
Structure description	Walker Lane structural zone

Ore body information

General form tabular

General form	tabular

Controls for ore emplacement

Shear zones

Comments on the geologic information

Quartz vein textures and inclusions indicate a gold-depositing boiling environment.

Economic information about the deposit and operations

Operation type	Surface-Underground
Development status	Past Producer
Commodity type	Metallic
Deposit size	Medium
Significant	Yes
Year of first production	1860
Year of last production	1930

Mining district

District name	Como District

Land status

Ownership category	BLM Administrative Area
Area name	Carson City BLM District
Ownership category	Private

Ownership information

Type Owner-Operator

Owner Royal Standard Minerals

Year 2006

Type	Owner-Operator
Owner	Royal Standard Minerals
Year	2006

Comments on the workings information

The district veins are developed by historic underground workings (shafts, adits, drifts) as well as by more recent drilling and surface exploration.

Comments on other economic factors

The property has had historical underground production of about 20,000 ounces of gold and 500,000 ounces of silver.
Royal Standard reports an open pit mineable resource of 40,000 ounces of gold in the central area of the property, No estimates of remaining reserves or resources are currently available.

Comments on development

In 2002, Royal Standard Minerals Inc. acquired the Como gold-silver property consisting of 47 (now 60) unpatented lode claims and five patented claims in the main historic Como District, which produced between the 1860s and 1930s. Since the 1960s several large companies, including St. Joe American, Amoco, Meridian Gold, Amax Gold Inc., and Anglo Gold Corp., have explored the property. Amax identified a low grade open pit resource, based on 46 holes. Anglo released the property in 2001 after drilling eight holes and completing considerable surface geologic mapping and geochemical sampling. Anglo's drilling program discovered a "new" high-grade vein system (0.45 opt over 10 feet within a mineralized zone that is 40 to 70 feet thick).
Royal Standard began follow up work based upon the previous exploration results and in February 2004 announced the completion of the evaluation of its Como Gold-Silver Project.

Past work has identified two bulk-mineable gold-silver targets requiring further work. Anglo Gold conducted perhaps the most intriguing work on the property in 2000, looking for a multi-million ounce deposit. Although they released the property in 2001, their drilling identified a high-grade vein system that with values of 0.45 opt over a 10-foot width with a thickness ranging from 40 to 70 feet. Surface rock chip samples on this vein have returned values up to 0.417 opt gold.

Reference information

Bibliographic references

Deposit

Cutler, H.C., "Como Nevada," Mining & Scientific Press, April 13, 1912, pp 539-540.
Deposit

Sirdevan, W.H, Report On Nevada Deep Mines Co, Unpublished Report, Item 6, File 181, NBMG
Deposit

Carlisle, H.C., Report on Como Mines Co, Unpublished Report, Item 3 File 181, NBMG.
Deposit

Stoddard, C, Carpenter, J.A., Mineral Resources of Storey and Lyon Counties, Nev (1950) NBMG Bull 49.
Deposit

Jerry Baughman, oral communication, 1999
Deposit

NBMG Bull 75
Deposit

Royal Standard Minerals Inc., website and press releases, 4/3/02, 2/1004
Deposit

NBMG MI-2002.
Deposit

VIkre, Peter and McKee, Edwin, 1994, Geology, alteration, and geochronology of the Como District, Lyon County, Nevada; Bulletin of the Society of Economic Geologists, vol.89, no.3, pp.639-646.
Deposit

Long, K.R., DeYoung, J.H., Jr., and Ludington, S.D., 1998, Database of significant deposits of gold, silver, copper, lead, and zinc in the United States; Part A, Database description and analysis; part B, Digital database: U.S. Geological Survey Open-File Report 98-206, 33 p., one 3.5 inch diskette.
Deposit

Royal Standard Minerals website 2006, http://www.royalstandardminerals.com

General comments

Subject category	Comment text
Deposit	Historically, mineralization in the district is contained in quartz veins of the Buckeye-Como vein system. Underground mine records show that the Buckeye-Como vein was mined along a continuous zone 720 feet long. Veins were 10-50 feet wide with up to 4 feet of soft crumbly quartz on the hanging wall and were developed along strike for more than 1600 feet. Ore is oxidized down to 250 level, below which veins were barren. Quartz vein is made up of hard white or slightly bluish-tinged quartz, banded in some places, with later clear quartz crystals filling cavities. The Elgin vein parallels the Como vein about a1000 feet to the south. Although the Elgin Vein has had minor recorded production, assays along the surface of the veil and drilling encountered high-grade gold-silver mineralization along an untested strike length of 3,000 feet. Additionally, Anglo?s drilling discovered a "new" high grade (0.45 opt over 10' within a mineralized zone that is 40-70' in thickness) vein system. RSM plans to test the western extension of the Elgin vein where it plunges under valley cover. Similarly encouraging assay results were obtained for mineralization along the Como vein, Palmyra vein/stockwork, and the Hully-Logan vein areas which offer targets for gold-silver resources that have not been drill tested.

Subject category

Comment text

Deposit

Historically, mineralization in the district is contained in quartz veins of the Buckeye-Como vein system. Underground mine records show that the Buckeye-Como vein was mined along a continuous zone 720 feet long. Veins were 10-50 feet wide with up to 4 feet of soft crumbly quartz on the hanging wall and were developed along strike for more than 1600 feet. Ore is oxidized down to 250 level, below which veins were barren. Quartz vein is made up of hard white or slightly bluish-tinged quartz, banded in some places, with later clear quartz crystals filling cavities.
The Elgin vein parallels the Como vein about a1000 feet to the south. Although the Elgin Vein has had minor recorded production, assays along the surface of the veil and drilling encountered high-grade gold-silver mineralization along an untested strike length of 3,000 feet. Additionally, Anglo?s drilling discovered a "new" high grade (0.45 opt over 10' within a mineralized zone that is 40-70' in thickness) vein system. RSM plans to test the western extension of the Elgin vein where it plunges under valley cover.
Similarly encouraging assay results were obtained for mineralization along the Como vein, Palmyra vein/stockwork, and the Hully-Logan vein areas which offer targets for gold-silver resources that have not been drill tested.

Reporter information

Type	Date	Name	Affiliation	Comment
Reporter	01-MAY-2004	LaPointe, D.D.	Nevada Bureau of Mines and Geology
Editor	01-SEP-2007	Schruben, Paul G.	U.S. Geological Survey	Converted from S&A FileMaker format to Oracle. Edit checks on rocks, units, and ages with Geolex search, and other fields.

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.

Maps centered on this site

Authoritative Nevada resources

These are landing pages for further research — the state agencies don't currently expose per-mine deep links.