Ashdown Mine Gold-Molybdenum Project

Producer in Humboldt county in Nevada, United States with commodities Gold, Silver, Molybdenum, Copper, Tungsten, Lead, Mercury
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Public Land Survey System information
  6. Commodities
  7. Materials information
  8. Alteration
  9. Mineral occurrence model information
  10. Host and associated rocks
  11. Nearby scientific data
  12. Geologic structures
  13. Ore body information
  14. Controls for ore emplacement
  15. Economic information about the deposit and operations
  16. Mining district
  17. Land status
  18. Ownership information
  19. Bibliographic references
  20. General comments
  21. Reporter information

Geologic information

Identification information

Deposit ID 10310474
MRDS ID M232645
Record type Site
Current site name Ashdown Mine Gold-Molybdenum Project
Alternate or previous names Ashdown Mine, Vicksburg Mine, Curley Luck gold property
Related records 10246381, 10044995

Comments on the site identification

  • This prospect encompasses the historic Ashdown Mine and Vicksburg Mine areas, MRDS records #M232645 and MRDS #M232655 from which material has been incorporated into this record and additional new material has been added.

Geographic coordinates

Geographic coordinates: -118.69545, 41.83015 (WGS84)
Elevation 1430
Relative position The Ashdown mine project is located about 110 miles northwest of Winnemucca and 10 miles southwest of Denio Junction in Humboldt County, Nevada.

Site location context

Political divisions (FIPS codes)

Humboldt(county)

Nevada(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Vicksburg Canyon(quadrangle 1:24,000 scale)

Denio(quadrangle 1:100,000 scale)

Vya(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Thousand-Virgin(hydrologic unit)

Black Rock Desert(hydrologic accounting unit)

Black Rock Desert-Humboldt(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 Humboldt

Public Land Survey System information

Meridian Township Range Section Fraction State
Mount Diablo 045N 029E 14 13 12 Nevada

Comments on the location information

  • The Ashdown gold-molybdenum project covers about 6 square miles and is controlled by 196 unpatented mining claims in the northern Pine Forest Range. Access to the property is gained by following a good improved dirt road about 10 miles west of Denio Junction off paved State Route 140 for about three miles to the southeast to the property. The project is located on the northwest flank of the Pine Forest Range.

Commodities

Commodity Importance
Gold Primary
Silver Primary
Molybdenum Primary
Copper Secondary
Tungsten Critical Secondary
Lead Tertiary
Mercury Tertiary

Comments on the commodity information

  • Ore Materials: free gold, pyrite, tetrahedrite, galena, native mercury, chalcopyrite, native copper, cinnabar, molybdenite, chalcocite
  • Gangue Materials: quartz, iron oxides

Materials information

Materials Type of material
Gold Ore
Pyrite Ore
Tetrahedrite Ore
Galena Ore
Mercury Ore
Chalcopyrite Ore
Copper Ore
Cinnabar Ore
Molybdenite Ore
Chalcocite Ore
Quartz Gangue

Alteration

  • (Local) Alteration associated with the mineralization is minimal .

Mineral occurrence model information

Model code 273
USGS model code 36a
Deposit model name Low-sulfide Au-quartz vein
Mark3 model number 27

Host and associated rocks

  • Host or associated Host
    Rock type Plutonic Rock > Granitoid > Granodiorite
    Rock type qualifier gneissic
    Stratigraphic age (youngest) Early Cretaceous
    Chronological age 102
    Dating method K-Ar
  • Host or associated Host
    Rock type Volcanic Rock (Aphanitic) > Pyroclastic Rock > Tuff
    Stratigraphic age (youngest) Early Cretaceous
    Chronological age 102
    Dating method K-Ar
  • Host or associated Host
    Rock type Volcanic Rock (Aphanitic) > Pyroclastic Rock > Tuff
    Rock type qualifier dacitic welded
    Stratigraphic age (youngest) Early Cretaceous
    Chronological age 102
    Dating method K-Ar

Nearby scientific data

(1) -118.69545, 41.83015

Economic information

Geologic structures

Type of structure Local
Structure description Fault zones

Ore body information

  • General form tabular

Controls for ore emplacement

  • Fault zones with pre- and post-ore movement controlled ore deposition. Analysis of both vein systems suggests that the veins occupy en echelon tension fractures that trend northwest and dip southwest, sub-parallel to the trend of the Pine Forest Range.

Economic information about the deposit and operations

Operation type Surface-Underground
Development status Producer
Commodity type Metallic
Deposit size Small
Significant Yes
Discovery year 1863
Year of first production 1860
Year of last production 1942
Production years 1860s-1940s

Mining district

District name Warm Springs District
District name Vicksburg District

Land status

Ownership category BLM Administrative Area
Area name Winnemucca BLM Administrative District

Ownership information

  • Type Owner-Operator
    Owner Win-Eldrich Mines Limited
    Year 2005
  • Type Owner-Operator
    Owner Golden Phoenix Minerals, Inc.
    Year 2005
  • Type Owner-Operator
    Owner PRS Enterprises
    Year 2005

Comments on the workings information

  • Historic mining was done predominantly by underground methods. Workings include 10 adits (up to 1500 feet long) and other underground workings as well as numerous shallow surface workings. The 1,880-foot Sylvia Sylvia decline was excavated in the 1970s-1980s.
    Golden Phoenix Minerals intends to conduct mining, processing, and reclamation operations. Mining of any potential ores will be by open pit and underground methods with extraction possibly being done by flotation and gravity separation methods. The main area of the Ashdown/Vicksburg camp is a labyrinth of roads and drill sites put in by American Copper and Nickel in the early 1980s.

Comments on other economic factors

  • The historic Ashdown Mine produced approximately 50,000 ounces of gold from ore that averaged 0.35 ounces per ton during operations from 1880 to 1942. The tonnage of ore mined from the adjacent Vicksburg mine was estimated at 500,000 tons with a combined copper-gold-silver value of $12/ton (1967).
    In the 1980s, the ACNC/OMI joint venture developed 325,000 tons of gold ore grading 0.152 ounces of gold per ton and 146,000 tons grading 2.74% molybdenum as well as a low grade molybdenum resource of 600,000 tons grading 1% molybdenum. A feasibility study completed in 1987 indicated that the calculated reserve is 497,000 tons of ore grading 0.115 ounces of gold per ton.
    Win-Eldrich Mines Limited reports that Ashdown contains a 146,000 ton mineral resource averaging 2.9 percent (or 58 pounds per ton) molybdenum and a separate gold deposit of 1.18 million tons averaging 0.125 ounces per ton gold, based on past economic evaluations.

Comments on development

  • The first claims were located in the area in 1863. Very little is recorded of the early history of the Ashdown Mine and early mining was hindered by isolation and hostility of the Bannack Indians. A small mill erected in 1864 was burned by the Indians in 1865. It is thought that the Ashdown Mine was operated during the 1880s. The Ashdown group of 16 claims was owned in the 1930s by C.C. Crow and leased to G. Mathewson. Development at that time consisted of 10 adits, one about 1500 feet long, and other workings totaling about 10,500 feet. Up to about 1942, when gold production was shut down from the L-208 War Act, production of about 52,000 ounces of gold had been reported from ore averaging 0.31 ounces of gold per ton. In 1954, 32 tons of tungsten ore containing about 1.0 % WO3 was reportedly produced from the Ashdown Mine, with no other details on the deposit or minerals, but this ore may have been mined at another property to the north and was only milled at the Ashdown mill. The Ashdown mine was owned in the 1960s by Vern Cannon. Most of the historic district production has come from this mine. The Vicksburg Mine area covers the Vicksburg vein, which lies 1100 feet north of outcrops of the Ashdown vein. It was discovered in 1863 and mined intermittently ever since.
    Modern exploration was first initiated in 1980 when American Copper and Nickel Company (ACNC), the U. S. subsidiary of International Nickel and Copper Company (INCO) entered into an agreement with the property owners to purchase the Ashdown Group of claims. After extensive negotiation, the owners sold their property to ACNC and received a royalty, which is still current today.
    In 1982 Outokumpu Mines, Inc. (OMI) a subsidiary of Outokumpu Oy, a large Finnish mining company, entered into a joint venture with ACNC to explore and develop Ashdown. Although the property was temporarily inactive at time of NBMG examination in 1984, the joint venture continued until 1985 with a large number of drill holes drilled into multiple targets in the western part of the mine area. They developed 325,000 tons of gold ore grading 0.152 ounces of gold per ton and 146,000 tons grading 2.74% molybdenum and a low grade molybdenum resource of 600,000 tons at 1%. A decline was sunk into the molybdenite orebody, and the new workings were reported to exceed 3000 feet. Tens of thousands of tons of molybdenite ore were stockpiled on the property and sampled by NBMG in 1984.
    In 1986 Westwater Resources Inc. entered into an agreement with ACNC/OMI to buy their interest in the Ashdown Mine in return for a retained net profits interest. Then in 1987 Westwater entered into a sales agreement with Toronto-based Win-Eldrich Mines Limited (WEX), and retained a 1% uncapped royalty. A feasibility study completed in 1987 indicated that the calculated reserve is 497,000 tons of ore grading 0.115 ounces of gold per ton. WEX further renegotiated the royalties to ACNC and OMI reducing them to a reasonable level. In 1988 and 1989, WEX undertook extensive exploration and drilling with the results expanding the resource to 1.07 million tons at 0.088 ounces of gold per ton. In 1990 Billiton Minerals, a subsidiary of Royal Dutch Shell, entered into an option to purchase agreement with WEX and began extensive drilling and metallurgical work. In 1991 Billiton completed its feasibility study and reported diluted reserves of 1.02 million tons at 0.077 ounces of gold per ton. Billiton did not exercise its option because Royal Dutch Shell decided to get out of the gold mining business. In 1992 North Lily Mining Company entered into an option to purchase agreement with WEX, completed 5 holes and performed minor metallurgical work. They did not exercise their option.
  • In the period from 1995 to 2002 declining gold prices caused a lack of interest in the project from potential joint venture partners. Several of the royalties disappeared including those with ACNC and OMI. With rising gold prices, interest in the property was renewed, and new agreements were reached between PRS Enterprises and Golden Phoenix Minerals, Inc. in 2003.
    Golden Phoenix announced in March 2004 that it was progressing in its permitting process for the Ashdown gold molybdenum property, now consisting of 187 mining claims, covering about 6 square miles controlled through a joint venture with Win-Eldrich Mines, Ltd. The plan calls for process for a pilot mill, designed to run about 100 tons per day of high-grade molybdenum ore and concurrent permitting for a production mill designed to process up to 1500 tons per day. The pilot mill will help the Company refine its recovery process for both gold and molybdenite ores. The Company reports that the starter feed for the pilot gravity and flotation recovery plant is currently stockpiled at the mine site. This material was previously mined for a large metallurgical test conducted more than ten years ago. It is estimated that considerable metal values lie in this stockpile, and the metal recovered could pay for this phase of the operation. Golden Phoenix plans to expand toward an open pit and a full underground mining operation once pilot mill production is underway and permitting is complete. Production of molybdenum concentrate at the mill from stockpiled ore was under way in 2006.

Reference information

Bibliographic references

General comments

Subject category Comment text
Deposit The gold and molybdenum mineralization on the Ashdown property is found in quartz veins that cross-cut diorite gneisses. In places, quartz is massive and in others, pegmatitic. Narrow, gently dipping (less than 40 degrees) quartz veins cut granodiorite, steepening downward; vein width varies from 2 to 10 feet, averaging 5 feet. Finely disseminated native copper occurs in the footwall below the quartz vein at the 400 foot level, with secondary enrichment of copper in seams in the gneissic host rock. Mineralization includes massive molybdenite, chalcopyrite, minor mercury, and other sulfides occurring in brecciated, iron-stained quartz veins. The property is located near a Jurassic granodiorite to granite intrusive, which underlies the northern part of the Pine Forest Range. Gold mineralization occurs as 20 to 100 micron flakes in the quartz vein, while molydenite mineralization occurs separately from the gold. Average grade of the gold ore previously reported from the 270 drill holes is about 0.125 opt while the molybdenum ore grade is about 2.9%.
Historical production at Ashdown was from a high-grade quartz vein system with an average length of 1000 feet and an average thickness of over ten feet. Underlying the gold system is a similar series of quartz veins containing high-grade molybdenite. Analysis of both vein systems suggests that the veins occupy en echelon tension fractures that trend northwest and dip southwest, sub-parallel to the trend of the Pine Forest Range. The gold mineralization is contained in two zones averaging about 12 feet thick each, often containing massive quartz, dipping 30-40 degrees southwest, sub parallel to the hill slope. The silver to gold ratio is 1 to 1. Similar large-scale quartz veins occur in Vicksburg Canyon, located just north of Ashdown, and Cherry Gulch, located just south of Ashdown. Vicksburg contains gold and molybdenum in drill cuttings, and Cherry Gulch contains gold and molybdenum anomalies in rock chip and stream sediment samples.
the quartz vein system at the Ashdown Mine is hosted in Jurassic aged metasediments and Cretaceous aged quartz diorite. These host rocks are unconformably overlain by Tertiary volcanics, which locally contain clasts of the Mesozoic rocks and the quartz vein system in a basal conglomerate. Since none of the volcanics are mineralized, the quartz vein system is thought to predate the Tertiary volcanic sequence. At the Vicksburg area adjacent to the Ashdown Mine, Triassic metasediments have been intruded by large masses of bull quartz from granitic sources which also outcrop within the area of the Vicksburg site.
the massive nature of the veins, which can be up to 30 feet thick, and the lack of significant epithermal indicator elements such as mercury and arsenic support the interpretation that the veins are part of a mesothermal system comparable to the Mother Lode vein system of the Sierra Nevada in California. Granodioritic host rocks were K/Ar-dated at 102 MA in 1969.
Mesothermal mineralization appears to be limited to Mesozoic crystalline rocks.A few miles to the north in the southern Pueblo Mountains, the Hall Mine, south of the Cowden Mine, contains showing of copper and molybdenum sulfides in metamorphic rocks, and the Cold Springs Mine about two miles north of Ashdown in the northern Pine Forest Range produced a small amount of tungsten and copper from a quartz vein system in quartz diorite.
No mineralization has been identified in the youngest of the Mesozoic intrusive rocks, a Cretaceous quartz monzonite. This unit forms Mahogany Mountain and Fisher Peak just south and southeast of the Ashdown Mine area. Mineralization occurs north, west and south of this rock unit. Early mineral rich fluids generated by the quartz monzonite magma, or by magmas of unexposed intrusive rocks, may be responsible for the mesothermal quartz vein mineralization in the northern Pine Forest Range.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-FEB-2005 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.

Authoritative Nevada resources

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