Copper Flat

Past Producer in Sierra county in New Mexico, United States with commodities Copper, Gold, Molybdenum, Silver
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. Mineral occurrence model information
  9. Host and associated rocks
  10. Nearby scientific data
  11. Ore body information
  12. Controls for ore emplacement
  13. Economic information about the deposit and operations
  14. Mining district
  15. Mineral rights holdings
  16. Land status
  17. Ownership information
  18. Production statistics
  19. Reserves and resources
  20. Workings at the site
  21. Links to other databases
  22. Bibliographic references
  23. General comments
  24. Reporter information

Geologic information

Identification information

Deposit ID 10150841
MRDS ID D000585
MAS/MILS ID 0350510055
Record type Deposit
Current site name Copper Flat
Alternate or previous names Hillsboro - Copper Flat, Sternberg Shaft, Hillsboro, Quintana

Geographic coordinates

Point of reference Ore Body
Geographic coordinates: -107.5417, 32.96821 (WGS84)
Elevation 1658
Location accuracy 1000(meters)

Site location context

Political divisions (FIPS codes)

Sierra(county)

New Mexico(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Hillsboro(quadrangle 1:24,000 scale)

Hatch(quadrangle 1:100,000 scale)

Las Cruces(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Caballo(hydrologic unit)

Rio Grande-Caballo(hydrologic accounting unit)

Rio Grande-Mimbres(hydrologic subregion)

Rio Grande(hydrologic region)

Geographic areas

Country State County
United States New Mexico Sierra

Public Land Survey System information

Meridian Township Range Section Fraction State
New Mexico 015 S 007 W 26 W 1/2 New Mexico

Commodities

Commodity Importance
Copper Primary
Gold Secondary
Molybdenum Secondary
Silver Secondary

Materials information

Materials Type of material
Bornite Unknown
Chalcopyrite Unknown
Magnetite Unknown
Molybdenite Unknown
Pyrite Unknown
Sphalerite Unknown
Tetrahedrite Unknown

Mineral occurrence model information

Model code 79
USGS model code 21a
Deposit model name Porphyry Cu-Mo
Mark3 model number 2

Host and associated rocks

  • Host or associated Host
    Rock type Plutonic Rock > Granitoid > Quartz Monzonite

Nearby scientific data

Ore Body (1) -107.5417, 32.96821

Economic information

Ore body information

  • Thickness 512M
    Length 366M
    Width 183M
    Area 259HA
    Depth to top 6M
    Field Value
    MAS Matrix # 1
    MAS Column # 1
    Type of Orebody #1 STOCKWORK
    Shape of Orebody #1 PIPELIKE
    Type of Orebody #2 DISSEMINATED
    Type of Orebody #3 BRECCIA FILL
    Primary mode of Origin UNKNOWN
    Primary Ore Control LITHOLOGY
    Secondary Ore Control IGNEOUS
    Degree of Wallrock Alter. UNKNOWN
    Type of Wallrock Alter. #1 UNKNOWN
    Minimum Depth to Top 6
    Avg. Thick. Unconsol. Mat. 5
    Min. Thick. Unconsol. Mat. 5
    Total Surface Area (HA) 259
    Date of Last Modification 970930

Controls for ore emplacement

  • Brecciation

Economic information about the deposit and operations

Operation type Surface
Development status Past Producer
Commodity type Metallic
Deposit size Small
Significant Yes
Discovery year 1877
Mining method Open Pit
Year of first production 1982
Plant type Beneficiation (Mill)
Plant subcategory Flotation
Milling method Flotation

Mining district

District name Hillsboro District
District name Las Animas mining district

Mineral rights holdings

Type of mineral rights Located Claim
Type of mineral rights Patented
Type of mineral rights Private Lease

Land status

Ownership category Private

Ownership information

  • Type Owner-Operator
    Owner Alta Gold Co.
    Interest 100
    Home office Utah
    Year 1994
    First year 1994
  • Type Owner-Operator
    Owner Gold Express Corp.
    Interest 100
    Home office Washington
    Year 1994
    Last year 1994
  • Type Owner-Operator
    Owner Quintana Minerals Corp.
    Interest 100
    Year 1980
    First year 1980
  • Type Lessee/Operator
    Owner Mercator Gold plc
    Interest 100
    Home office London, UK
    Year 2009
    First year 2009

Comments on the ownership information

  • Mill Designed And Built For 13605 Mtpd (350 Day/Yr) Capacity. Alta Gold Purchased Property In Feb 1994 From Gold Express Corp. For $7.8 Million Cash.

Production statistics

  • Year 1982
    Description Mrach 82 To June 82 Ore Production 1200000 St Ore
  • Year 1982
    Description Silver Produced Form Ore 55966 Tr Oz Ag
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Trace Ore Silver Silver 1740737.41g
  • Year 1982
    Description Gold Producer Form Ore 2301 Tr Oz Au
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Trace Ore Gold Gold 71569.1g
  • Year 1982
    Description Copper Production From Ore 7400000 Pounds Cu
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major Copper Copper 3356583.53mt

Comments on the production information

  • For Product A, A 94% Copper Recovery Was Used To Calculate The Concentrate Output Tonnage. For Product E, A 92% Copper Recovery Was Used To Calculate The Concentrate Output Tonnage.

Reserves and resources

  • Type In-situ
    Estimate year 1994
    Indicated 59500000mt ore
    Demonstrated 59500000mt ore
    Total resources 59500000mt ore
    Commodity Subtype Grade units Group Importance Year
    Copper Cu 0.371 wt-pct Copper Major 1994
    Silver Ag 1.7 g/mt Silver Minor 1994
    Gold Au 0.127 g/mt Gold Minor 1994
    Molybdenum Mo 0.012 wt-pct Molybdenum Minor 1994
  • Type In-situ
    Estimate year 1998
    Reserves 50550000mt
    Remarks Alta Gold 1998 10K, p. 11.
    Commodity Subtype Grade units Group Importance Year
    Copper 0.45 wt-pct Copper Primary 1998
    Silver 2.3 g/mt Silver Secondary 1998
    Gold 0.14 g/mt Gold Secondary 1998
    Molybdenum 0.015 wt-pct Molybdenum Secondary 1998
  • Type In-situ
    Estimate year 1982
    Reserves 54000mt
    Remarks USBM & Noske '87
    Commodity Subtype Grade units Group Importance Year
    Copper Cu 0.42 wt-pct Copper Primary 1982
    Silver Ag 3 g/mt Silver Secondary 1982
    Gold Au 0.01 g/mt Gold Secondary 1982
    Molybdenum Mo 0.012 wt-pct Molybdenum Secondary 1982
  • Type In-situ
    Estimate year 1989
    Reserves 63000mt
    Remarks Titley '92
    Commodity Subtype Grade units Group Importance Year
    Copper Cu 0.7 wt-pct Copper Primary 1989
  • Type In-situ
    Estimate year 1996
    Demonstrated 53631854mt ore
    Total resources 53631854mt ore
    Commodity Subtype Grade units Group Importance Year
    Copper Cu 0.364 wt-pct Copper Major 1996
  • Type In-situ
    Estimate year 1997
    Demonstrated 53632000mt ore
    Commodity Subtype Grade units Group Importance Year
    Copper Cu 0.425 wt-pct Copper Major 1997
    Silver Ag 2.09 g/mt Silver Minor 1997
    Gold Au 0.14 g/mt Gold Minor 1997
    Molybdenum Mo 0.013 wt-pct Molybdenum Minor 1997

Comments on the reserve resource information

  • Orig Eval In 6/78. Revised In 3/79. Updated In 5/83. Operational Data Based Partially On Quintana Minerals Feasibility Study Dtd 7/16/76; Other Data Is From Published Sources. Original Operation Came On Line In March 1982 And Was Shut Down In June 1982. See Mas File Sternberg Shaft Mas Seq# 0350510137 (Old Claim Listing-?) This Property Is On The Copper Flat Property But Is Located In Section 35: Also See Mas File Seq 0350510138 For Old Plant Property File. Proven + Probable Ore Reserves, 12/31/96; Adit Cap Based On 3 Months Production In 1982 Of 1.2 Mst (4.354 Mmt/Yr). Alta Gold Co. Is Presently Evaluation The Potential Of A Joint Venture, Spin-Off Or Sale Of This Property & Its Other Base Metal Properties So That Alta Gold Co. May Focus On Its Gold Development And Production.
  • M6=M1+M2+M3+M4. Matrix Six Contains The Total Reserves. Matrices One Through Three Contain Portions Of The Proven And Probable Reserves Which Are Proposed In Development Schedule One For Mining During Various Time Intervals In The Mine Life. Matrix Four Contains Possible Reserves Which Are Not Proposed For Mining In Development Schedule One. See Matrix One Remarks For Explanation Of Relationships Between Reserve Matrices. M9c4=M1:M9c4+M9c5+M9c6=M1+M2+M3+M4=M6.

Workings at the site

  • Type of workings Surface
    Area 41HA
    Field Value
    MAS Development Schedule # 1
    Mining Record # 1
    Status of Mining Method ESTIMATE
    Mining Method OPEN PIT
    Percent Waste Rock 51.9
    Avg. Overburden Thickness 6
    Primary Material Cover M-HARD ROCKS
    Hardness of Ore M-HARD ROCKS
    Avg. Bench Height (meters) 12
    Max. Pit Slope (degrees) 40
    Capacity 19047
    Capacity Units MT ORE/DAY
    Preprod. Stripping Vol. 650
    Unit Production Cost 1.27
    Units of Production $/MT ORE
    Operating Days per Year 250
    Operating Shifts per Day 3
    Year of Information 1982
  • Type of workings Surface
    Area 41HA
    Field Value
    MAS Development Schedule # 1
    Mining Record # 2
    Status of Mining Method ESTIMATE
    Mining Method OPEN PIT
    Percent Waste Rock 55
    Avg. Overburden Thickness 6
    Primary Material Cover M-HARD ROCKS
    Hardness of Ore M-HARD ROCKS
    Avg. Bench Height (meters) 12
    Max. Pit Slope (degrees) 40
    Capacity 19047
    Capacity Units MT ORE/DAY
    Unit Production Cost 1.5
    Units of Production $/MT ORE
    Operating Days per Year 250
    Operating Shifts per Day 3
    Year of Information 1982
  • Type of workings Surface
    Area 41HA
    Field Value
    MAS Development Schedule # 1
    Mining Record # 3
    Status of Mining Method ESTIMATE
    Mining Method OPEN PIT
    Percent Waste Rock 66.6
    Avg. Overburden Thickness 6
    Primary Material Cover M-HARD ROCKS
    Hardness of Ore M-HARD ROCKS
    Avg. Bench Height (meters) 12
    Max. Pit Slope (degrees) 40
    Capacity 19047
    Capacity Units MT ORE/DAY
    Unit Production Cost 2.28
    Units of Production $/MT ORE
    Operating Days per Year 250
    Operating Shifts per Day 3
    Year of Information 1982

Comments on other economic factors

  • Mill Designed And Built For 13605 Mtpd (350 Day/Yr) Capacity.
  • Original Mine Designed For 19047 Mtpd (250 Day/Yr) Capacity.

Reference information

Bibliographic references

  • Deposit

    Kilburn, J., 1996, Alta Gold to develop Copper Flat porphyry; The Northern Miner, June 24 issue, p. 1.

  • Reserve-Resource

    Pay Dirt Magazine (Southwestern Edition). Alta Gold Acquires Copper Flat, Plans Startup In 1996. Mar 1994, P. 3a.

  • Deposit

    McLemore, V.T., Munroe, E.A., Heizler, M.T. and McKee, C., 2000, Geology and evolution of the Copper Flat porphyry-copper system, Hillsboro mining district, New Mexico; in Geology and Ore Deposits 2000: The Great Basin and Beyond, Geological Society of Nevada, Symposium Program with Abstracts, p. 63.

  • Reserve-Resource

    News Release, Alta Gold Co., Announces Year-End Reserves April 9, 1996. P3.

  • Reserve-Resource

    Alta Gold Co., 1995 Annual Report, Pp. 6, 14, 15.

  • Deposit

    Dunn P G 1982 - Geology of the Copper Flat Porphyry Copper deposit, Hillsboro, Sierra County, New Mexico: in Titley S R 1983 Advances in Geology of the Porphyry Copper Deposits, Southwestern North America University of Arizona Press, Tucson pp 313-325

  • Reserve-Resource

    Alta Gold Co., 1996 Form 10-K Report, Pp. 9, 11.

  • Deposit

    Kuellmer, F., 1955, Geology of a Disseminated copper deposit near Hillsboro, New Mexico: New Mexico Institute of Mining and Tech., Circ. 34

  • Deposit

    Socorro Symposium 6/75 (Rock Descrip).

  • Deposit

    Lewis, J.D. and Smith, R.C., Hillsboro-Copper Flats Deposit, New Mexico Sept. 26, 1977.

  • Deposit

    Personal Communication, Bob Donegan, Mgr., Quintana Minerals

  • Deposit

    Tipton, Wm., Personal Communication, District Geologist, Blm Las Cruces.

  • Deposit

    Bennett, H.J., Et Al. An Economic Appraisal Of The Supply Of Copper From Primary Domestic Sources. Bumines Ic 8598, 1973, 156 P.

  • Deposit

    Dataquest, Inc. The Equipment Value Guide. Palo Alto, Ca, 1982.

  • Deposit

    The Mining Record. Rio Gold Completes Acquisition Of. Dec. 6, 1989. Pp. 16,17,18.

  • Deposit

    Southwestern Pay Dirt. Copper Flat Reopening Apparently High-Centered By Finances. June, 1991. P.14a.

  • Deposit

    Titley, Spencer R., In "Advances In Geology Of The Porphyry Copper Deposits Southwestern North America", 1982, University Of Arizona Press.

  • Deposit

    Southwestern Pay Dirt. Three Startup Copper Companies Cranking Up In Southwest. January, 1993. Pp.8a-12a.

  • Deposit

    North, R.M., and McLemore, V.T., 1988, A classification of the precious metal deposits of New Mexico, in Schafer, R.W., Cooper, J.J., and Vikre, P.G., eds., Bulk mineable precious metal deposits of the western United States: Reno, Nevada Geological Society

  • Deposit

    McLemore, V.T., Munroe, E.A., Heizler, M.T. and McKee, C., 1999, Geochemistry of the Copper Flat porphyry and associated deposits in the Hillsboro mining district, Sierra County, New Mexico, USA: Journal of Geochemical Exploration, v. 67, p. 167?189.

  • Deposit

    Long, K.R., 1995, Production and reserves of Cordilleran (Alaska to Chile) porphyry copper deposits, in Pierce, F.W., and Bolm, J.G., eds., Porphyry copper deposits of the American Cordillera: Tucson, Arizona Geological Society Digest 20, p. 35-68.

General comments

Subject category Comment text
Deposit Orig Eval In 6/78. Revised In 3/79. Updated In 5/83. Operational Data Based Partially On Quintana Minerals Feasibility Study Dtd 7/16/76; Other Data Is From Published Sources. Original Operation Came On Line In March 1982 And Was Shut Down In June 1982. See Mas File Sternberg Shaft Mas Seq# 0350510137 (Old Claim Listing-?) This Property Is On The Copper Flat Property But Is Located In Section 35: Also See Mas File Seq 0350510138 For Old Plant Property File.
Deposit Associated Minerals: apatite, azurite/malachite, biotite, bornite, chalcocite, chalcopyrite, chlorite, chrysocolla, cuprite, epidote, fluorite, galena, magnetite, molybdenite, pyrite, sericite, sphalerite, tetrahedrite, zeolite
Deposit Associated Rock: breccia, jasperoid, latite, latite porphyry, quartz monzonite, skarn;basalt, conglomerate, dolomite, limestone, mudstone, quartz monzonite porphyry, quartzite, rhyolite pyroclastics, sandstone, schist, shale;andesite flow, andesite pyroclastics

Reporter information

Type Date Name Affiliation Comment
Reporter 30-SEP-97 Buckingham, David A. U.S. Bureau of Mines
Reporter 18-NOV-83 New Mexico Bureau Of Mines And Mineral Resources New Mexico Bureau of Mines and Mineral Resources
Reporter 30-SEP-97 Buckingham, David A. U.S. Bureau of Mines
Reporter 01-AUG-74 King, Robert U. U.S. Geological Survey
Updater 29-DEC-09 Anderson, Claire U.S. Geological Survey

Beyond USGS

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

External references