Aura Minerals Inc.

Aura Minerals Inc.

September 04, 2012 09:15 ET

Aura Minerals Announces Positive Feasibility Study on Its Serrote da Laje Property

VANCOUVER, BRITISH COLUMBIA--(Marketwire - Sept. 4, 2012) - Aura Minerals Inc. ("Aura Minerals" or the "Company") (TSX:ORA) is pleased to announce it has received the results of the feasibility study (the "FS") on its wholly owned Serrote da Laje ("Serrote") property located near the city of Arapiraca in the state of Alagoas, Brazil.

The FS, prepared under the direction of Micon International Limited ("Micon"), comprises contributions from Micon and other consultants, such as SNC Lavalin-Minerconsult. The FS describes the scope, design and viability of developing Serrote based on an open pit mining operation with a copper concentrator operating at 19,000 tonnes per day and producing approximately 66 million pounds of copper per year.

Highlights (all currency in US dollars)

  • Open pit mine and copper concentrator processing 7 million tonnes per annum;
  • After-tax NPV (8%) of $191 million and IRR of 19.4% based on consensus metal price forecasts;
  • Capital cost of $420 million;
  • Life of mine cash cost of $1.40 per pound of payable copper;
  • Production of 831 million pounds of copper and 171,000 ounces of gold over a 13 year mine life;
  • Magnetite recovery and oxide ore treatment identified as future opportunities;
  • Satellite deposits remain open and may offer potential to extend mine life or lead to expansion;
  • Mining Concession and Environmental Installation License obtained;
  • Community resettlement negotiations underway;
  • Projected production starting in mid-2015;
  • Project financing discussions underway.

Jim Bannantine, President and CEO of Aura Minerals stated: "Completion of the Serrote project feasibility study is a significant milestone for Aura Minerals. The study demonstrates a Project that is commercially viable and beneficial to the region. Serrote can provide a domestic source of copper concentrate for Brazil, in relative proximity to the smelter in Bahia State, avoiding the need to import copper concentrate for these volumes. The Project is also 150 kilometers from the international port of Maceio and benefits from ample existing sources of water and power as well as the 225,000 person city of Arapiraca, 15 kilometers from the mine. The mine and plant will also provide hundreds of permanent jobs for the developing Northeast region of Brazil in Alagoas State. The Project benefits significantly from both Alagoas State and Federal tax benefits that target both the Northeast region and the Serrote da Laje Project, specifically. The Company has initiated negotiations with adjacent communities, with potential project lenders and is targeting construction to begin in the second half of 2013 and production start-up by mid-2015. We intend to finance this Project with a combination of public institutions, export/import banks and multilateral agencies, as well as commercial banks, who specialize in mining finance."

Summary Project Description:

The Serrote Project has been designed as a conventional open pit operation using large diameter blast-hole drills, hydraulic excavators and truck haulage. Proven and Probable mineral reserves are based on mining of the Serrote resource only. Resources estimated for the satellite deposits Caboclo, Rogerio and Zeze are not included in the reserves and remain a future opportunity.

The proposed process plant has a throughput capacity of 19,000 tonnes per day (7 million tonnes per annum), and consists of 3-stage crushing, ball milling, and conventional flotation to produce a copper concentrate product. Copper concentrate will be trucked either approximately 150 km and shipped from the Maceio port for offshore sales, or approximately 450 km to the smelter located near Salvador, Bahia, Brazil. Oxide mineralization will be stockpiled separately for treatment in a possible future heap leach operation. The Project design includes space provision for a possible magnetite recovery circuit.

Mineral Reserves:

The open pit design developed for calculating reserves is based on $3.00/lb copper and $1,250/oz gold prices, 84% recovery for copper and 65% gold recovery. Although the Company believes the magnetite asset has potential economic value, it is not included in the reserve calculations. The reserves shown below are calculated based on industry standard pit optimization techniques, allowance for pit slope criteria, ramps and detailed pit designs:

Classification Material
t x 1,000
Proven 1 50,805 0.54 0.10 7.09 25.26
Probable1,2 34,667 0.50 0.09 7.82 22.77
Total Reserves 85,471 0.52 0.10 7.38 24.25
Inferred Material 1,3 1,027 0.36 0.07 3.35 16.73
Waste Materials
Oxide Material 4,3 14,996 0.48 0.10 4.77
Soil 5 610
Un-mineralized Rock 213,293
Total Waste 6 228,899
Total Material 315,397
Strip Ratio 7 2.7
1 Above a NSR cut-off of $7.45 / tonne and inside the designed ultimate pit.
2 Includes 1,745k tonnes of additional low grade material as dilution.
3 Treated as waste in the Feasibility Mine Plans.
4 Oxide material above 0.3% copper is stockpiled separately as a future opportunity.
5 Soil is stockpiled for use in reclamation.
6 Total does not included Inferred material.
7 Strip Ratio is (Inferred Material + Total Waste) / Total Reserves.

Mineral Resource:

As part of the FS, the Serrote da Laje resource was updated and is described below. Resources are inclusive of reserves. Oxide material is reported separately, as processing of oxide material is not currently included in the project design basis.

Category Type Cut-off
(% Cu)
('000 lbs)
('000 oz)
('000 lbs)
Measured Oxide 0.12 14,513 0.44 140,077 0.10 44.7 4.6 1,460,473
Sulphide 0.12 63,319 0.51 718,771 0.11 220.5 8.7 12,083,844
Combined 0.12 77,832 0.50 858,848 0.11 265.2 7.9 13,544,317
Indicated Oxide 0.12 3,734 0.51 41,868 0.10 12.2 4.3 357,452
Sulphide 0.12 55,894 0.48 596,779 0.08 150.1 7.8 9,637,430
Combined 0.12 59,628 0.49 638,647 0.08 162.3 7.6 9,994,882
Oxide 0.12 18,247 0.45 181,945 0.1 57 4.5 1,817,925
Sulphide 0.12 119,213 0.50 1,315,550 0.1 370.6 8.3 21,721,274
Combined 0.12 137,460 0.49 1,497,495 0.1 427.5 7.8 23,539,199
Inferred Oxide 0.12 306 0.24 1,612 0.06 0.6 3.0 20,477
Sulphide 0.12 5,024 0.35 38,633 0.06 9.2 3.1 345,992
Combined 0.12 5,330 0.34 40,245 0.06 9.8 3.1 366,469

A detailed description of the resources for the satellite deposits will be included in the FS. The Caboclo-Rogerio satellite deposit includes a Measured and Indicated Mineral Resource of 10,056 kt sulphide material with 0.50% Cu grade, and 857 kt oxide material with 0.56% Cu grade, based on a 0.15% Cu cut-off grade. Minerals Resources that are not Mineral Reserves do not have demonstrated economic viability.

Production Plan:

Production is scheduled to start in mid-2015, ramping up over a six month period to an annual rate of 7 Mtpa.
Below is a summary of the average annual production.

Description Year 1 Average
2 to 12
Year 13 Total
Waste (including oxide)1 kt 15,605 18,919 113 232,000
Total Mill Feed kt 6,000 7,000 2,450 85,500
Cu Grade % 0.74 0.51 0.40 0.52
Au Grade g/t 0.13 0.09 0.07 0.10
Cu Production (M lb) M lb 81.9 66.4 18.0 831
Au Production (koz) koz 15.9 13.8 3.5 171
1 Also includes material required to be stripped in dump and stockpile footprints.

Capital Cost:

The capital cost is estimated at $420 million, including a $36 million contingency. Cost breakdown is summarized below:

Description Millions of US dollars
Mining 50
Process Plant 155
Infrastructure On-site 34
Infrastructure Off-site 15
Direct Costs $254
Project Indirect Costs 51
Owner Costs 67
Indirect Costs $118
Subtotal Direct and Indirect $372
Total Contingency 36
Total Project Capital Cost - pre-tax $408
Taxes and duties 44
Tax recoveries (32)
Total Project Capital Cost - net of recoverable taxes $420

Operating Cost:

The life-of-mine operating cost, net of recoverable taxes, is estimated at $13.04 per tonne of ore milled or $1.40 per pound of payable copper as summarized below.

Area $/tonne
Cu lb
Mining $5.27 $0.57
Processing $4.87 $0.52
General & Administrative $0.70 $0.08
Transportation and other $0.77 $0.08
Smelting and freight $3.27 $0.35
Gold revenue credits ($1.84) ($0.20)
Total Operating Costs $13.04 $1.40

Economic Analysis:

The financial model was prepared in real terms with all cash flows expressed in second quarter 2012 terms. Estimates are in the currency of origin with 85% of capital expenditures and 68% of operating expenses denominated in Brazilian Reais. The exchange rate applied was 2.03 BRL per USD reflecting the Company's current estimate of the appropriate Reais exchange rate at purchasing power parity.

Project returns are determined on an unlevered basis with a net present value of $191 million at 8% and an internal rate of return of 19.4%. The returns are on an after tax basis and include significant benefits from applicable tax incentive programs. Projected cash flows are summarized below:

Cash Flow Summary
(Millions of US dollars)
(Ramp up
2016 to
2019 to
Copper revenue $2,316 $112 $777 $1,427
Gold revenue 158 7 50 101
Government royalties (51) (2) (17) (31)
Smelting and freight (279) (11) (88) (180)
Net smelter return $2,143 $105 $722 $1,317
Mining (451) (16) (129) (306)
Processing (416) (12) (94) (310)
General and administration (60) (2) (13) (45)
Transportation and other (66) (3) (21) (42)
Sustaining capital and closure (85) (4) (24) (56)
Income taxes (102) (4) (31) (68)
Free cash flow $964 $65 $409 $490

Metal pricing assumptions are based on analyst consensus pricing with the following forecasted prices applied:

Description 2015 2016 2017 2018 2019 2020 Long
Copper ($/lb) $3.43 $3.17 $3.09 $3.00 $2.92 $2.83 $2.75
Gold ($/oz) $1,486 $1,373 $1,348 $1,324 $1,299 $1,275 $1,250

Permitting and Communities:

The Project has received the Environmental Installation License which allows construction to commence, and also the Mining Concession which is a prerequisite for obtaining the Operation License. Some project modifications have been made since the Installation License and the Mining Concession were obtained on September 2, 2009 and October 20, 2011, respectively. Therefore some updates will be required in the environmental licensing records and in the development plan (Plano de Aproveitamento Econômico) approved by the Brazilian mining authority (DNPM). The Company considers the modifications to be improvements, ultimately reducing the impacts of the Project, and does not expect the update approval process to hinder project development.

Presentations of the project development and associated community relations plan have been made to the adjacent and affected communities, and negotiations regarding resettlement are underway. Community support for the project continues to be positive.

Project Opportunities:

Magnetite recovery: The life-of-mine mill feed averages 7.4% contained magnetite. The metallurgical testwork program that was completed for the FS included investigations of magnetite recovery, and it was concluded that 92% recovery of magnetite is achievable, producing an average of 520 thousand tonnes/year of iron ore concentrate containing 65-66% iron. Existing transportation infrastructure includes a railway located 7 km from the Serrote plant site which connects to the Suape port (450 km to north) and Inácio Barbosa port (226 km to south). This railway is a concession of Transnordestina Logística S/A and is under refurbishment. The Company will pursue partnering with companies interested in the opportunity to invest in installing and operating a circuit for recovery of magnetite from the copper concentrator tailings, which will be disposed at the tailings dam on areas suitable for future reclaim.

Oxide material: A total of 15 million tonnes of oxide material containing 0.48% copper will be mined in the Serrote pit and stockpiled for potential future treatment by leaching. Leach testwork to date is limited, and will be investigated further in the next phases of the Project. Studies will consider synergies with the resources from Caboclo satellite deposits. Oxides from Serrote could potentially be trucked to Caboclo and sulphides from Caboclo trucked to Serrote taking advantage of the round trip, minimizing haulage costs.

Satellite deposits: The satellite deposits Caboclo-Rogerio and Zeze, located approximately 15 km north of Serrote, are excluded from the FS production plan. Baseline studies have been initiated to support potential future addition of these resources to the operation in Serrote.

Technical Disclosure

The NI 43-101 Technical Report supporting the FS is being prepared under the direction of Micon and by leading independent industry professionals, all Qualified Persons under NI 43-101. The Qualified Person for Aura Minerals is Dale Tweed, P. Eng., Vice President, Projects, who has reviewed and approved this news release. William Lewis, P.Geo. of Micon has also reviewed and approved this news release.

The NI 43-101 Technical Report supporting the FS, including a description of the Project resources, mine plan, metallurgy, capital costs, operating costs and financial analysis will be filed with the appropriate regulatory authorities within 45 calendar days of the date of this news release.

About Aura Minerals

Aura Minerals is a Canadian mid-tier gold and copper production company focused on the exploration, development and operation of gold and base metal projects in the Americas. The Company's producing assets include the San Andres gold mine in Honduras, the Sao Francisco and Sao Vicente gold mines in Brazil and the copper-gold-silver Aranzazu Mine in Mexico. The Company's core exploration asset is the feasibility-stage copper-gold-iron ore Serrote Project in Brazil. The Company also has the Inaja iron ore project currently optioned to Vale.

For further information, please visit Aura Minerals' web site at

Cautionary Note

This news release contains forward-looking information and forward-looking statements ("forward-looking statements"). All statements, other than of historical fact, that address activities, events or developments that the Company believes, expects or anticipates will or may occur in the future, including, without limitation, development of the Serrote project and the FS are forward-looking statements. These statements generally are identified by words such as "believes", "expects", "may", "will", "should", "anticipate" and similar language, or convey estimates and statements that describe the Company's future plans, objectives or goals. Since forward-looking statements are based on assumptions and address future events and conditions, by their very nature they involve inherent risks and uncertainties, many of which are beyond the Company's ability to control or predict. Factors that could cause actual results or events to differ materially from current expectations include, among other things, without limitation, failure to obtain necessary permits, currency fluctuations between the US dollar and the Brazilian Reais, failure to establish estimated mineral reserves or resources, its failure to meet estimated production levels, the failure to realize expected margins and valuations, changes in world copper and gold prices and other risks discussed in the section entitled "Risk Factors" in the Company's Annual Information Form. Readers are cautioned not to place undue reliance on forward-looking statements, which speak only as of the date thereof. The Company does not undertake to update any forward-looking statement that may be made from time to time except in accordance with applicable securities laws.

In making the forward-looking statements the Company has applied several material assumptions which may prove to be incorrect, including, but not limited to, that all required third party approvals will be obtained for the development, construction and production of its properties, there being no significant disruptions affecting operations, whether due to labour disruptions, supply disruptions, power disruptions, damage to equipment or otherwise; permitting, development and expansion proceeding on a basis consistent with the Company's current expectations; currency exchange rates being approximately consistent with current levels; certain price assumptions for copper and gold; production forecasts meeting expectations; the accuracy of the Company's current mineral resource and reserve estimates; labour and materials costs increasing on a basis consistent with the Company's current expectations; that any additional required financing will be available on reasonable terms; and assumptions made and judgments used in engineering and geological interpretation.

There can be no assurance that forward-looking statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements.

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