Hillsboro - Copper Flat

Site Name

Primary: Hillsboro - Copper Flat
Secondary: Sternberg Shaft
Secondary: Hillsboro
Secondary: Copper Flat
Secondary: Quintana

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Commodity

Primary: Copper
Secondary: Silver
Secondary: Molybdenum
Secondary: Gold

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Location

State: New Mexico
County: Sierra
District: Las Animas mining district

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Land Status

Land ownership: Private
Note: the land ownership field only identifies whether the area the mine is in is generally on public lands like Forest Service or BLM land, or if it is in an area that is generally private property. It does not definitively identify property status, nor does it indicate claim status or whether an area is open to prospecting. Always respect private property.

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Holdings

Type: Private Lease
Type: Patented
Type: Located Claim

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Workings

Type: Surface

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Ownership

Owner Name: Mercator Gold plc
Percent: 100.0
Home Office: London, UK
Info Year: 2009
Years: 2009 -

Owner Name: Quintana Minerals Corp.
Percent: 100.0
Info Year: 1980
Years: 1980 -

Owner Name: Gold Express Corp.
Percent: 100.0
Home Office: Washington
Info Year: 1994

Owner Name: Alta Gold Co.
Percent: 100.0
Home Office: Utah
Info Year: 1994
Years: 1994 -

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Production

Year: 1982
Description: Mrach 82 To June 82 Ore Production 1200000 St Ore
Year: 1982
Description: Silver Produced Form Ore 55966 Tr Oz Ag
Year: 1982
Description: Gold Producer Form Ore 2301 Tr Oz Au
Year: 1982
Description: Copper Production From Ore 7400000 Pounds Cu

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Deposit

Record Type: Deposit
Operation Category: Past Producer
Deposit Type: Porphyry Cu
Plant Type: Beneficiation (Mill)
Plant Subtype: Flotation
Operation Type: Surface
Mining Method: Open Pit
Milling Method: Flotation
Year First Production: 1982
Discovery Year: 1877
Years of Production:
Organization:
Significant: Y
Deposit Size: S

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Physiography

General Physiographic Area: Intermontane Plateaus
Physiographic Province: Basin And Range Province
Physiographic Section: Mexican Highland

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Mineral Deposit Model

Model Name: Porphyry Cu-Mo

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Orebody

Not available

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Structure

Not available

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Alterations

Not available

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Rocks

Not available

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Analytical Data

Not available

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Materials

Unknown: Tetrahedrite
Unknown: Sphalerite
Unknown: Pyrite
Unknown: Molybdenite
Unknown: Magnetite
Unknown: Chalcopyrite
Unknown: Bornite

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Comments

Comment (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

Comment (Deposit): Associated Minerals: apatite, azurite/malachite, biotite, bornite, chalcocite, chalcopyrite, chlorite, chrysocolla, cuprite, epidote, fluorite, galena, magnetite, molybdenite, pyrite, sericite, sphalerite, tetrahedrite, zeolite

Comment (Economic Factors): Mill Designed And Built For 13605 Mtpd (350 Day/Yr) Capacity.

Comment (Ownership): 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.

Comment (Reserve-Resource): 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.

Comment (Economic Factors): Original Mine Designed For 19047 Mtpd (250 Day/Yr) Capacity.

Comment (Production): 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.

Comment (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.

Comment (Reserve-Resource): 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.

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References

Reference (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.

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

Reference (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.

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

Reference (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

Reference (Deposit): The Mining Record. Rio Gold Completes Acquisition Of. Dec. 6, 1989. Pp. 16,17,18.

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

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

Reference (Deposit): Southwestern Pay Dirt. Copper Flat Reopening Apparently High-Centered By Finances. June, 1991. P.14a.

Reference (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

Reference (Reserve-Resource): Alta Gold Co., 1995 Annual Report, Pp. 6, 14, 15.

Reference (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.

Reference (Reserve-Resource): News Release, Alta Gold Co., Announces Year-End Reserves April 9, 1996. P3.

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

Reference (Deposit): Dataquest, Inc. The Equipment Value Guide. Palo Alto, Ca, 1982.

Reference (Deposit): Tipton, Wm., Personal Communication, District Geologist, Blm Las Cruces.

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

Reference (Deposit): Personal Communication, Bob Donegan, Mgr., Quintana Minerals

Reference (Reserve-Resource): Alta Gold Co., 1996 Form 10-K Report, Pp. 9, 11.

Reference (Deposit): Socorro Symposium 6/75 (Rock Descrip).

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

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