Saturday, September 26, 2026
MiningNewsTerminal
Saturday, September 26, 2026 Admin

IMG.TO ·

Iamgold’S Pre-Feasibility Study FOR the Boto GOLD Project Demonstrates Potential Low-Cost, Long-Life Operation

Economic Studies

NEWS RELEASE

TSX: IMG NYSE: IAG

IAMGOLD’S PRE-FEASIBILITY STUDY FOR THE BOTO GOLD PROJECT

DEMONSTRATES POTENTIAL LOW-COST, LONG-LIFE OPERATION

All amounts are in US dollars, unless otherwise indicated.

Toronto, Ontario, February 12, 2018 – IAMGOLD Corporation (“IAMGOLD” or the “Company”) today

announced positive results from a Pre-feasibility Study ("PFS") for its Boto Gold Project (Project) in

Senegal, West Africa. The results, which outline an economically viable project, justify the commencement

of a Feasibility Study to further optimize the project development design and improve project economics.

PRE-FEASIBILITY HIGHLIGHTS

 Indicated Res ources of 1.9 million ounces grading 1.60 g/t Au

 Proven and Probable Reserves of 1.4 million ounces grading 1.64 g/t Au

 Mine Life of 13.5 years with mill th roughput of 2.0 million tonnes per annum

 Life of Mine (LOM) average annual production of nearly 100,000 oz, with higher production in the

early years of operation

 LOM direct cash costs of $707/oz an d all-in sustaining costs of $829/oz

 At $1,275/oz gold price, after-tax Internal Rate of Return of 13.3% and a Net Present Value of

$104 million (6% discount rate)

 Initial capital expenditures of $249 million

Steve Letwin, President and CEO of IAMGOLD, said “Boto lies on a mineralized trend that is host to

several significant producing gold mines. The team ha s worked exceptionally hard to advance this project

from the initial discovery to a potential development project with a long life and attractive all-in sustaining

costs. It is important to understand that this is a work in progress, and although still short of our

investment criteria typical for West Africa, the project provides excellent optionality at higher gold prices.

We are continuing to aggressively optimize the project design to improve the overall economics.

Importantly, the feasibility study currently underway and due for completion in the second half of 2018 uses

a 25% higher mill throughput as the base case, which will accordingly increase annual gold production and

has the potential for improved project returns. We continue to aggressively explore priority targets to

enhance the total resource inventory, which would generate a positive impact on project economics and

mine life.”

The PFS was completed jointly by IAMGOLD and Lycopodium Minerals Canada Ltd., with inputs from

technical studies completed by other consultants and has an effective date of December 31, 2017. The

PFS represents a comprehensive study of the technical and economic viability of a mineral project that has

advanced to a stage where a preferred mining method has been established and an effective method of

mineral processing has been determined. IAMGOLD is using the PFS to identify the preferred

development option to demonstrate economic viability of the Project, to support Mineral Reserve

disclosure, and to identify additional work recommended to support the completion of a feasibility study.

Technical studies to support the completion of the feasibility study have commenced, with the study

scheduled for completion in the second half of 2018.

A technical report summarizing the PFS will be filed on SEDAR within 45 days of the date of this news

release.

2

PFS HIGHLIGHTS

USD Currency used with exchange rate of: CAD$ = US$0.7692

MINERAL RESOURCES

The Mineral Resource estimate used as the basis for the study is summarized below.

Mineral Resources – December 31, 2017

Classification

Tonnes

(000)

Grade

(g/t Au)

Contained Ounces

(000)

Indicated 37 408 1.60 1,922

Inferred 10 981 1.66 594

Notes:

1. CIM Definition Standards were followed for classification of Mineral Resources.

2. Mineral Resources reported at a cut-off grade of 0. 42 g/t Au for oxide and 0.54 g/t Au for fresh material.

3. Mineral Resources are constrained within a pit shell estimated using long-term gold price of $1,500 per

ounce, and a US$/C$ exchange rate of 1:1.30.

4. Mineral Resources are inclusive of Reserves quoted below.

MINERAL RESERVES

The tonnes, grades, and classification of the Mineral Reserves captured within the PFS mine plan are

summarized below.

Mineral Reserve – December 31, 2017

Tonnes Grade Contained Ounces

Classification (000) (g/t Au) (000)

Proven - - -

Probable 26,841 1.64 1,415

Proven & Probable 26,841 1.64 1,415

Waste within Designed Pit 175,700

Total Tonnage within Designed Pit 202,500

Notes:

1. Reserves estimated assuming open pit mining methods

2. Reserves are based on a gold price of $1,200/oz

3. Fixed process recovery of 89.3%

4. Mining costs ($/t processed): $15. 00/t. Processing costs: $14.76/t. G&A (Include refining cost): $3.55.

Project Economics and Key Parameters

Mining Capacity 18.0 Mtpa

Milling Capacity 2.0 Mtpa

LOM Average Annual Gold Production 95,000 oz.

LOM Average Recovery Rate 89.3%

Mine Life 13.5 years

LOM Average Direct Cash Costs $707/oz

LOM Average AISC $829/oz

Average Grade 1.64 g/t Au

Average LOM Strip Ratio 6.5:1

Estimated Initial Capital Expenditure (millions) $249

Gold Price Assumption used in financial analysis $1,275/oz

After-tax NPV (6%) (millions) $104

After-tax IRR 13.3%

Payback Period 6.0 years

3

MINING AND PROCESSING

The PFS study has identified the preferred development option to be a conventional truck and shovel open

pit mining operation, and has determined an effective method of mineral processing to be a processing

circuit incorporating primary crushing, grinding, gravity concentration and cyanide leaching, followed by

gold recovery using carbon-in-pulp, stripping and electrowinning.

Open pit mining includes approximately 15 Mt of stripping and preproduction mining during a two year pre-

production period followed by 13.5 years of production mining along with stockpile reclaim in the final years

of the operation. Maximum mining rate is 18 Mt per annum. The average grade is 1.64 g/t Au and the

LOM stripping ratio is 6.5:1.

FUTURE WORK

The PFS recommended the completion of a feasibility study to validate and detail the elements of the

development concept set out in the PFS, and which would include additional drilling, engineering studies

and environmental studies, including hydrological, hydrogeological and geotechnical analyses. The

recommended feasibility study work has already been initiated and is expected to be completed in the

second half of 2018, using a base case processing rate of 2.5 Mtpa versus the 2.0 Mtpa used for the

prefeasibility study. In addition to the feasibility study, we continue to conduct exploration activities on the

Boto exploration concession to evaluate high priority targets on trend for additional mineral resources.

QUALIFIED PERSONS

The 2017 Boto Gold PFS was prepared by IAMGOLD and Lycopodium Minerals Canada Ltd. and

incorporates the work of IAMGOLD and Lycopodium Qualified Persons (QPs) (as defined under National

Instrument 43-101). Lycopodium Qualified Persons are independent of IAMGOLD and have reviewed and

approved this news release. IAMGOLD Qualified Persons are not independent of IAMGOLD and have

reviewed and approved this news release. The affiliation and areas of responsibility for each Qualified

Person involved in preparing the 2017 Boto PFS, upon which the technical report will be based, are:

Lycopodium QPs

 N. Lincoln, P. Eng., Project infrastructures, permitting, investment and operational costs and

economical model

 R. Willis, P. Eng., Metallurgical testing and mineral processing

 W. Muir P. Eng. (Knight Piésold Ltd.), Tailings and water management

 G. Zurowski, P. Eng. (AGP Mi ning Consultants), Mine design, capital and operating costs, reserve

estimate

IAMGOLD QPs

 V. Blanchet, P.Eng., Data verificati on, and mineral resource estimate

 H. Fisette, P.Eng., Site description, historical setting, drilling, sample preparation and analysis and

security, data verification, and mineral resource estimate

The information in this news release was reviewed and approved by Craig MacDougall, P.Geo., Senior

Vice President, Exploration for IAMGOLD. Mr. MacDougall is a Qualified Person as defined by National

Instrument 43-101.

Forward-Looking Information

All Mineral Reserve and Mineral Resources estimates reported by the Company were estimated in

accordance with the Canadian National Instrument 43-101 and the Canadian Institute of Mining,

Metallurgy, and Petroleum Definition Standards (May 10, 2014). These standards differ significantly from

the requirements of the U.S. Securities and Exchange Commission. Mineral Resources which are not

Mineral Reserves do not have demonstrated economic viability.

4

This document contains "forward-looking information" within the meaning of Canadian securities legislation

and "forward-looking statements" within the meaning of the United States Private Securities Litigation

Reform Act of 1995. This information and these statements, referred to herein as "forward-looking

statements" are made as of the date of this document. Forward-looking statements relate to future events

or future performance and reflect current estimates, predictions, expectations or beliefs regarding future

events and include, but are not limited to, statements with respect to:

(i) the estimated amount and grade of Mineral Resources and Mineral Reserves;

(ii) the PFS representing a viable development option for the Project;

(iii) estimates of the capital costs of constructing mine facilities and bringing a mine into production, of

sustaining capital and the duration of financing payback periods;

(iv) the estimated amount of future production, both produced and metal recovered; and,

(v) estimates of operating costs and total costs, net cash flow, net present value and economic returns

from an operating mine.

Any statements that express or involve discussions with respect to predictions, expectations, beliefs,

plans, projections, objectives or future events or performance (often, but not always, using words or

phrases such as "expects", "anticipates", "plans", "projects", "estimates", "envisages", "assumes",

"intends", "strategy", "goals", "objectives" or variations thereof or stating that certain actions, events or

results "may", "could", "would", "might" or "will" be taken, occur or be achieved, or the negative of any of

these terms and similar expressions) are not statements of historical fact and may be forward-looking

statements.

All forward-looking statements are based on IAMGOLD's or its consultants' current beliefs as well as

various assumptions made by them and information currently available to them. The most significant

assumptions are set forth above, but generally these assumptions include:

(i) the presence of and continuity of metals at the Boto Gold Project at estimated grades;

(ii) the geotechnical and metallurgical characteristics of rock conforming to sampled results; including

the quantities of water and the quality of the water that must be diverted or treated during mining

operations;

(iii) the capacities and durability of various machinery and equipment;

(iv) the availability of personnel, machinery and equipment at estimated prices and within the

estimated delivery times;

(v) currency exchange rates;

(vi) metals sales prices and exchange rate assumed;

(vii) appropriate discount rates applied to the cash flows in the economic analysis;

(viii) tax rates and royalty rates applicable to the proposed mining operation;

(ix) the availability of acceptable financing under assumed structure and costs;

(x) anticipated mining losses and dilution;

(xi) metallurgical performance;

(xii) reasonable contingency requirements;

(xiii) success in realizing proposed operations;

(xiv) receipt of permits and other regulatory approvals on acceptable terms; and

(xv) the fulfillment of environmental assessment commitments and arrangements with local

communities.

Although management considers these assumptions to be reasonable based on information currently

available to it, they may prove to be incorrect. Many forward-looking statements are made assuming the

correctness of other forward looking statements, such as statements of net present value and internal

rates of return, which are based on most of the other forward-looking statements and assumptions herein.

The cost information is also prepared using current values, but the time for incurring the costs will be in the

future and it is assumed costs will remain stable over the relevant period.

5

By their very nature, forward-looking statements involve inherent risks and uncertainties, both general and

specific, and risks exist that estimates, forecasts, projections and other forward-looking statements will not

be achieved or that assumptions do not reflect future experience. We caution readers not to place undue

reliance on these forward-looking statements as a number of important factors could cause the actual

outcomes to differ materially from the beliefs, plans, objectives, expectations, anticipations, estimates

assumptions and intentions expressed in such forward-looking statements. These risk factors may be

generally stated as the risk that the assumptions and estimates expressed above do not occur as forecast,

but specifically include, without limitation: risks relating to variations in the mineral content within the

material identified as Mineral Resources and Mineral Reserves from that predicted; variations in rates of

recovery and extraction; the geotechnical characteristics of the rock mined or through which infrastructure

is built differing from that predicted, the quantity of water that will need to be diverted or treated during

mining operations being different from what is expected to be encountered during mining operations or

post closure, or the rate of flow of the water being different; developments in world metals markets; risks

relating to fluctuations in the Canadian dollar relative to the US dollar; increases in the estimated capital

and operating costs or unanticipated costs; difficulties attracting the necessary work force; increases in

financing costs or adverse changes to the terms of available financing, if any; tax rates or royalties being

greater than assumed; changes in development or mining plans due to changes in logistical, technical or

other factors; changes in project parameters as plans continue to be refined; risks relating to receipt of

regulatory approvals; delays in stakeholder negotiations; changes in regulations applying to the

development, operation, and closure of mining operations from what currently exists; the effects of

competition in the markets in which IAMGOLD operates; operational and infrastructure risks and the

additional risks described in IAMGOLD’s Annual Information Form filed with SEDAR in Canada (available

at www.sedar.com ) for the year ended December 31, 2016 and in the Corporation's Annual Report Form

40-F filed with the U.S. Securities and Exchange Commission on EDGAR (available at

https://www.sec.gov/edgar/searchedgar/companysearch.html. IAMGOLD cautions that the foregoing list of

factors that may affect future results is not exhaustive.

When relying on our forward-looking statements to make decisions with respect to IAMGOLD, investors

and others should carefully consider the foregoing factors and other uncertainties and potential events.

IAMGOLD does not undertake to update any forward-looking statement, whether written or oral, that may

be made from time to time by IAMGOLD or on our behalf, except as required by law.

About IAMGOLD

IAMGOLD ( www.iamgold.com) is a mid-tier mining company with four operating gold mines on three

continents. A solid base of strategic assets in No rth and South America and West Africa is complemented

by development and exploration projects and continu ed assessment of accretive acquisition opportunities.

IAMGOLD is in a strong financial position with extensive management and operational expertise.

For further information please contact:

Ken Chernin, VP Investor Relations, IAMGOLD Corporation

Tel: (416) 360-4743 Mobile: (416) 388-6883

Laura Young, Director, Investor Relations, IAMGOLD Corporation

Tel: (416) 933-4952 Mobile: (416) 670-3815

Toll-free: 1-888-464-9999 [email protected]

Please note:

This entire news release may be accessed via fax, e-mail, IAMGOLD's website at www.iamgold.com and through CNW Group’s website

at www.newswire.ca. All material information on IAMGOLD can be found at www.sedar.com or at www.sec.gov.

Si vous désirez obtenir la version française de ce communiqué, veuillez consulter le

http://www.iamgold.com/French/accueil/default.aspx.