Miami East

Site Name

Primary: Miami East
Secondary: Miami Property
Secondary: Miami Pit
Secondary: Miami Concentrator
Secondary: Miami Leach
Secondary: Magma No. 2 Tailings
Secondary: Miami No. 2 Tailings
Secondary: Old Dominion
Secondary: Old Miami
Secondary: Miami Tailings

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Commodity

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

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Location

State: Arizona
County: Gila
District: Globe-Miami 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: Patented

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Workings

Type: Underground

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Ownership

Owner Name: BHP Billiton Group
Percent: 100.0
Info Year: 2009

Owner Name: Broken Hill Proprietary Co. Ltd.
Home Office: Australia
Info Year: 1996
Years: 1996 -

Owner Name: Magma Copper Co.
Company ID: 200825
Percent: 100.0
Home Office: San Manuel, Az 85631
Info Year: 1987

Owner Name: Cities Services
Home Office: Arizona
Info Year: 1981

Owner Name: Newmont Mining Corporation
Percent: 100.0
Info Year: 1983
Years: 1983 -

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Production

Year: 1993
Year: 1993
Material type: Sx-Ew Cathode Copper 6220 Mt Cathode Cu Produced
Year: 1992
Mined: 3410000.000 mt
Material type: Tailings Mined
Year: 1992
Material type: Sx-Ew Cathode Copper 5350 Mt Cathode Cu Produced
Year: 1991
Mined: 3539000.000 mt
Material type: Tailings Mined
Year: 1991
Material type: Sx-Ew Cathode Copper 4536 Mt Cathode Cu Produced
Year: 1990
Mined: 3156000.000 mt
Material type: Tailings Mined
Year: 1990
Material type: Sx-Ew Cathode Copper 4417 Mt Cathode Cu Produced
Year: 1989
Mined: 1244000.000 mt
Material type: Tailings Mined
Year: 1989
Material type: Sx-Ew Cathode Copper 4029 Mt Cathode Cu Produced
Year: 1988
Material type: Sx-Ew Cathode Copper 4445 Mt Cathode Cu Produced
Year: 1987
Material type: Sx-Ew Cathode Copper 4257 Mt Cathode Cu Produced
Year: 1986
Material type: Sx-Ew Cathode Copper 3451 Mt Cathode Cu Produced
Year: 1984
Mined: 4060.000 mt
Material type: Cu
Year: 1984
Material type: Sx-Ew Cathode Copper 4061 Mt Cathode Cu Produced
Year: 1985
Material type: Sx-Ew Cathode Copper 3656 Mt Cathode Cu Produced
Year: 1983
Material type: Sx-Ew Cathode Copper 4214 Mt Cathode Cu Produced
Year: 1982
Material type: Sx-Ew Cathode Copper 4673 Mt Cathode Cu Produced
Year: 1981
Material type: Sx-Ew Cathode Copper 4634450 Kilograms Cu Annually
Year: 1979
Material type: Sx-Ew Cathode Copper 5731550 Kilograms Cu Annually
Year: 1980
Material type: Sx-Ew Cathode Copper 5072470 Kilograms Cu Annually
Year: 1978
Material type: Sx-Ew Cathode Copper 5308470 Kilograms Cu Annually

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Deposit

Record Type: Deposit
Operation Category: Past Producer
Deposit Type: Porphyry Copper
Operation Type: Underground
Mining Method: Filled Stopes - Horiz Cut and Fill W/Tailings
Milling Method: Flotation
Discovery Year: 1969
Years of Production:
Organization:
Significant: Y
Deposit Size: L

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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

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Orebody

Form: Type of Orebody #1 : DISSEMINATED Shape of Orebody #1 : MASSIVE Type of Orebody #2 : FISSURE VEIN Primary mode of Origin : HYDROTHERMAL Primary Ore Control : IGNEOUS Secondary Ore Control : FAULTING Degree of Wallrock Alter. : MODERATE Type of Wallrock Alter. #1 : INTERM ARGILLIC Date of Last Modification : 830502

Name: Miami
Form: Ore Genesis: Hydrothermal Orebody Typer: Disseminated, Vein (Lode) Ore minerals: Charcocite, Bornite, Covellite, Malachite, Azurite, Chrysocolla Class of Ore: Sulfide, Carbonate, Silicate, Native Gangue mineral: Cuprite

Form: ore minerals: Chalcocite class of ore: sulfide, oxide lithostratigraphic unit: gila conglomerate

Form: Total Surface Area (HA) : 200Date of Last Modification : 910418

Form: Total Surface Area (HA) : 85 Previous Surface Area (HA) : 85 Reclaimed Surface Area (HA): 15 Date of Last Modification : 920629

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Structure

Type: R
Structure: Eastward Dipping Normal Faults Steeply Dipping Joints Trending NE and NW

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Alterations

Alteration Type: L
Alteration: Silicate Alteration: Potassic, Argillic, Sericitic, And Propylitic

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Rocks

Name: Schist
Role: Host
Description: sequence of coarse grained quartz-muscovite schist, fine grained quartz-sericite-chlorite schist and some fine grained amphibole schist
Age Type: Host Rock
Age Young: Mesoproterozoic

Name: Quartz Monzonite
Role: Host
Description: multiple phase-predominantly a porphyritic quartz-monzonite (adamellite), includes granodiorite and later phase granite porphyry
Age Type: Host Rock
Age Young: Paleocene

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Analytical Data

Not available

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Materials

Ore: Molybdenite
Ore: Galena
Ore: Chalcopyrite
Ore: Pyrite
Ore: Gold
Ore: Silver
Unknown: Azurite
Unknown: Bornite
Unknown: Chalcocite
Unknown: Chrysocolla
Unknown: Copper
Unknown: Cuprite
Unknown: Malachite
Unknown: Covellite
Unknown: Quartz
Unknown: Sericite

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Comments

Comment (Development): In May 2007, the Miami project was associated with BHP Billiton's 100%-owned Pinto Valley project (profile #005523) which was being put back in production. The Pinto Valley Miami Unit had Measured and Indicated in-situ leach ore resources totaling 214 million mt grading 0.32% Cu. (BHP Billiton WS ,07)In June 1999, BHP reported that the Miami in-situ leach and Miami No.2 tailings leach operations closed operations. (Arizona Mining Association ,99)In 1998, BHP was reported to be extracting Cu from a 35 million mt tailings pile and revegetating the land with the reprocessed tailings. The Old Miami and Old Dominion were part of a $100 million clean-up campaign in the Pinal Creek area. (Australian ,98)In 1994 Magma launched a feasibility study aimed at expanding reserves and production at the mine. Results were expected during the fourth quarter of 1995, with the potential expansion to begin during 1997 at a rate of 25,000 st/y Cu. (Magma ,94 AR ,95)

Comment (Reference): Data taken from other MRDS Sources: Magma No. 2 Tailings 10137065 Miami Leach 10161493 Miami East 10048778 Miami Concentrator 10283121 Miami Property 10112449 Miami Pit 10209726

Comment (Production): 1910-50: THE MIAMI MINE WAS IN PRODUCTION. 1960's: IN SITU SOLUTION LEACHING BEGAN. 1982: THE OPEN PIT MINE AND CONCENTRATOR WERE SHUT DOWN, ALTHOUGH THE LEACHING AND SOLVENT-EXTRACTION PLANTS REMAINED IN OPERATION. 1984: THE MINE AND MILL RESUMED FULL PRODUCTION IN JULY. (KNW ,84) 1988: THE PINTO VALLEY DIVISION OF MAGMA BEGAN CONSTRUCTION OF A TAILINGS RECYCLING FACILITY. (PDS ,89)1989: Tailings treatment started at the end of April at a rate of 8,000 st/y of cathode copper from tailings. SXEW processing recovered 54% of the contained copper during the year.

Comment (Deposit): Down Thrown Segment Of The Miami Fault

Comment (Development): July 1988, Acquired Substantially All Assets Of Inspiration Copper Company (Subsidiary Of Inspiration Resources Corporation)

Comment (Geology): Copper Mineralization Happened During The Last Stages Of Granitic Intrusions.

Comment (Production): Production Data From Magma Copper Co. Sec Form 10-K Reports For The End Of Years 1989 Through 1991.

Comment (Reserve-Resource): M9c4=M1c1. Quant-Grade Matrix 1 Based On Stated Reserves In Magma Copper Co. Sec Form 10-K Report, Dec 31, 1991, P. 18.

Comment (Economic Factors): The No. 2 Tailings Project Is A Hydraulic Mine Operation Of The Old Miami No. 2 Tailings Pile. Four Mining Stations (Mining Sets) Each Consisting Of Two 10-Cm-Diam Monitors, Eductor Pumps, And Slurry Booster Pumps. Two Mining Sets Operate At Anyone Time To Mine 10,900 Mtpd Ore. Two Mining Sets Operate From Different Parts Of The Tailings Pile To Produce A Blended Slurry. The Slurry Is Pumped A Average Distance Of 610 M (Max Dist = 1,220 M) To The Processing Plant. At The Processing Plant, The Tailings Are Leached In A Thickener. Then The Pregnant Leach Solution Is Decanted Off The Thickener, And Is Clarified, Before Being Pumped To The Nearby Sx-Ew Plant. The Pls Flow Sent To The Sx-Ew Is 189.3 L/Sec Containing 1.628 G/L Copper. This Pls Joins 195.6 L/Sec Pls, Containing 0.82 G/L Cu, From The Miami In Situ Leach Operation (Seq No 0040070053) At The Solvent Extraction Collection Pond. The Sx Plant Processes 384.8 L/S Pls With An Average Feed Grade Of 1.217 G/L Cu. The Electrowinning Tank House (Ew) Produces A Total Of 37,230 Kgs Cathode Copper Per Day, Of Which 24,490 Kgs Cu Is Attributed To The No. 2 Tailings Project. Feed Rec 101 Is For Grade Of Pls Flow From The No. 2 Tailings Processing Plant Sent To The Sx-Ew Plant. The Blended Feed Of The Total Sx Plant Feed Is 1.217 G/L.

Comment (Geology): Copper Minerals Given By Company As A Mix Of 55% Oxides And 45% As Sulfides.

Comment (Deposit): The Pregnant Solution (Pls) From The In Situ Join The Pls From The No. 2 Tailings Project (Seq No 0040070706). The No.2 Tailings Project Will Close In 1998. The In Situ Leach Is Anticipated To Continue Until 2011. Property Updated In July 1987 Property. Updated In June 1992

Comment (Economic Factors): The K1 Record Represents The Sx-Ew Plant With The Combined Flows Of 189.3 L/Sec From The No. 2 Tailings Project & 195.6 L/Sec From The In Situ Leach, For A Total Of 384.8 L/Sec. Pls. K2 Record Represents The Period After The No. 2 Tailings Project Is Closed In 1998, The The Pls Flow Is Reduced To 195.6 L/Sec. The Capital (Working Capital) And Operating Costs Given In Rec. K1 Is Attributed Only To The Cost Related To The Pls Flow And Copper Produced From The In-Situ Operation.

Comment (Economic Factors): Reserves Are For The Tailings Reclaim Proj., Insitu Project Resource Difficult To Quantify. The Pls Grade Listed In Feed Rec 1, Line 1 Is The Pls Feed Grade From The In-Situ Leach Only. The Blended Feed Grade Is 1.217 G/L Copper.

Comment (Production): The Recovery Given Is The Sx-Ew Plant Recovery, Not The Leach Recovery From The Mine. That Recovery Is Not Known. Product Leach Solutions Are Collected At The 1000 Foot Level Of The Mine, Pumped To The Surface & Treated By A Solvent-Extraction Electrowinning Plant.

Comment (Production): History: Main Ore Body Consists Of Caved Ground Above The Old Miami Block-Cave Operation. Leached-Capping And Many Isolated Blocks Of Sulfide Are Being Leached.

Comment (Reserve-Resource): Quantity Matrix 1 Consists Of Material That Was Broken-Up By The Blockcave Operation. M9c4=M1c1. The Reserve Grade Represents Mt Copper Recovered For 20 Yrs Based On A Constant Pls Flow From The Mine Of 195.6 L/Sec, 0.82 G/L Cu, 92% Plt Recovery, And 360 Op Days Per Yr.

Comment (Deposit): The No. 2 Tailings Project Is A Hydraulic Mine Operation Of The Old Miami No. 2 Tailings Pile. Four Mining Stations (Mining Sets) Each Consisting Of Two 10-Cm-Diam Monitors, Eductor Pumps, And Slurry Booster Pumps. Two Mining Sets Operate At Anyone Time To Mine 10,900 Mtpd Ore. Two Mining Sets Operate From Different Parts Of The Tailings Pile To Produce A Blended Slurry. The Slurry Is Pumped A Average Distance Of 610 M (Max Dist = 1,220 M) To The Processing Plant. At The Processing Plant, The Tailings Are Leached In A Thickener. Then The Pregnant Leach Solution Is Decanted Off The Thickener, And Is Clarified, Before Being Pumped To The Nearby Sx-Ew Plant. The Pls Flow Sent To The Sx-Ew Is 189.3 L/Sec Containing 1.628 G/L Copper. This Pls Joins 195.6 L/Sec Pls, Containing 0.82 G/L Cu, From The Miami In Situ Leach Operation (Seq No 0040070053) At The Solvent Extraction Collection Pond. The Sx Plant Processes 384.8 L/S Pls With An Average Feed Grade Of 1.217 G/L Cu. The Electrowinning Tank House (Ew) Produces A Total Of 37,230 Kgs Cathode Copper Per Day, Of Which 24,490 Kgs Cu Is Attributed To The No. 2 Tailings Project.

Comment (Reserve-Resource): Reserves Are For The Tailings Reclaim Proj., Insitu Project Resource Difficult To Quantify.

Comment (Production): The In Place Grade Of The Ore Is 3.14% Cu; After Mining (Dilution) The Grade Is 2.8%. A New Grade For Moly Has Also Been Estimated Based On The New Miami East Feed To The Mill. Ore Must Be Blended With The Pinto Valley Ore Before Milling Average Grades For The Blended Miami East And Pinto Valley Ore Are Shown In This Set. The Actual Grade Of This Ore Is Presented In The Q Data Set. Development At Miami East Suspended Indefinitely As Of January 7, 1987.

Comment (Reserve-Resource): The Reserves Shown In Q-Matrix 1 Are The Current Reserves The Mining Company Considers Available As Of July 1983. The Figure In Q-Matrix 2 Was The Originally Estimated Reserves. Because Of Very Incompetent Rock Conditions The Company No Longer Considers The Original Figure An Accurate Estimate Of Obtainable Reserves. The Cu Grade Has Increased And Is Shown; The Grades Of The Byproducts Have Not Yet Been Determined; Consequently, The Original Grades For These Elements Are Shown. It Is Likely, However, The Grades Of The Accessory Commodities Will Also Improve.

Comment (Deposit): Refs. 1c 7990 USGS Map 260/Mesa/(1:250000 Series) Ariz B Co. Reserves In Apache-Blk Forest-Giant Cactus-Globe-Ire Mines Property Update July 1987

Comment (Reserve-Resource): Development Has Been Postponed Indefinitely.

Comment (Economic Factors): The In Place Grade Of The Ore Is 3.14% Cu; After Mining (Dilution) The Grade Is 2.8%. A New Grade For Moly Has Also Been Estimated Based On The New Miami East Feed To The Mill. Ore Must Be Blended With The Pinto Valley Ore Before Milling Average Grades For The Blended Miami East And Pinto Valley Ore Are Shown In This Set. The Actual Grade Of This Ore Is Presented In The Q Data Set.

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References

Reference (Deposit): Arizona Paydirt. Miami East Underground Mine Is To Begin Production In July. Jan. 1982, Pp. 7-10.

Reference (Workings): Skillings 1/75 (Tailings Fill)

Reference (Deposit): Newmont Mining Corp. Annual Report 1982. P. 3.

Reference (Workings): Cities Service Annual Report 1974 (Production Plans)

Reference (Workings): Mining Magazine 9/75 (Development, Production Rate)

Reference (Workings): Skillings 7/75 (Development)

Reference (Workings): Paydirt 4/70 (Development)

Reference (Workings): Trip Notes From Arizona Dmr 10/73 (Development)

Reference (Reserve-Resource): Magma Copper Co., 1994 10-K, P.19.

Reference (Reserve-Resource): Magma Copper Company Sec Form 10-K Rept, Dec 31, 1993, P. 18 Copper Industry Of Arizona. P. 49.Z

Reference (Deposit): American Metal Market 1/5/70 (Exploration)

Reference (Deposit): Arizona Republic 12/30/69,P. 25 (Exploration)

Reference (Deposit): Wall Street Journal 4/21/69 (Exploration)

Reference (Geology): Me 5/75 (Ore Body Size,Development, Mining Method, Milling)

Reference (Reserve-Resource): Magma Copper Co. Sec Form 10-K Report, Dec 31, 1992, P. 21.

Reference (Deposit): Walenga, Karen. Project To Recover 125 Million Pounds Of Copper. Paydirt Mag. (Southwestern Ed.). March 1988, Pp. 4a-6a.

Reference (Deposit): Shank, R., Senior Engineer, Pinto Valley Copper Co.,Personal Contacts, July 22 And 26, 1983.

Reference (Deposit): Zach, R. Pinto Valley Copper Co., Personal Contact, July 21,1983.

Reference (Geology): Olmsted and Johnson, 1966, In Titley and Hicks, Univ Of Az Press.

Reference (Geology): The Porter GeoConsultancy webpage for the Globe-Miami District contain detailed descriptions of the geology. Accessed on 7/27/2010 http://www.portergeo.com.au/index.asp
URL: http://www.portergeo.com.au

Reference (Reserve-Resource): Magma Copper Co., 1994 10-K, P.19-20.

Reference (Reserve-Resource): Magma Copper Company 1993 Annual Report. P. 8.

Reference (Deposit): Magma Copper Co. Sec Form 10-K Reports For The End Of Years 1989-1991.

Reference (Production): Mc Waters, Tom. Developing Magma'S Tailings Leach Operation Min. Eng. Mag., Sep. 1990, Pp. 1075-1080.

Reference (Reference): Hardwick,W R,1967, Fracturing A Deposit With Nuclear Explosives and Recovering Copper By The In-Situ Leach Method, Bur Of Mines Ic 6996, P6-8. (Description Of Leach Equipment)

Reference (Production): At The Miami Mine, Miami Copper Company, Gila County, Arizona, Bur Of Mines 8271, 96p. (Leach Operation Description)

Reference (Production): Fletcher,J B,1971, In-Place Leaching, Miami Mine, Miami,Arizona, Aime Preprint 71-As-40, 13p.(Description Of Operation. Solution Strengths)

Reference (Production): Baer,R L,1977, Trip Notes From Visit To Miami Mine, Bom-IFOC September, 1977 (Detailed Information About Operation)

Reference (Geology): Ransome, L,1919, The Copper Deposits Of Ray and Miami, Arizona: USGS Prof Pa 115. (Lands and Deposit Description)

Reference (Geology): Peterson,N P,1962, Geology and Ore Deposits Of The Globe-Miamidistrict, Arizona: USGS Prof Pa 342. (Deposit Maps and Cross-Sections)

Reference (Deposit): Burgin,L B,1976 Time Required In Developing Selected Copper Mines, Bur Of Mines Ic 8702, P60-84(Production Records and Historical Development)

Reference (Orebody): Peterson, N.P. (1962), Geology and ore deposits of the Globe-Miami District, Arizona, USGS PP 342: 83-88.

Reference (Reserve-Resource): Titley, S.R., 1992, Evidence for crustal controls of metallogeneis in epigenetic ores of the Southern Cordillera, United States and Mexico: Society of Mining, Metallurgy, and Exploration Annual Meeting Preprint 920-210, 11p.

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