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Gunnison Copper Announces Preliminary Economic Assessment of Open Pit Mining at its Flagship Gunnison Project in Arizona’s Copper Belt Webinar Scheduled for Friday November 15th at 12pm ET

Economic Studies Marketing Announcement

NEWS RELEASE

Gunnison Copper Announces Preliminary Economic Assessment of Open Pit Mining at

its Flagship Gunnison Project in Arizona’s Copper Belt

Webinar Scheduled for Friday November 15th at 12pm ET

November 14, 2024

Gunnison Copper Corp. (TSX: GCU) (FSE: 3XS) (OTCQB: EXMGF) ("GCC" or the “Company”) is

pleased to announce the results of a Preliminary Economic Assessment (“PEA”) on its 100%-owned

Gunnison Project in the Cochise Mining District, Arizona. The Gunnison Project is presented as a

conventional open pit and heap leach operation which will produce finished copper cathode for domestic

U.S. consumption. All dollar amounts are in US dollars and “Tons” refer to U.S. short tons (1 short ton

equals approximately 0.91 metric tonnes).

The Company will present at a webinar hosted by Adelaide Capital on Friday November 15th at 12pm

ET. Questions can be submitted during the session or in advance to [email protected]. The webinar

will be livestreamed on the Adelaide Capital YouTube Channel, where a replay will be available after the

event: https://bit.ly/adcap-youtube. Register here: https://streamyard.com/watch/heaHcYsvWeCw.

Highlights of the PEA (United States Dollars)

 The Gunnison Project, a fully vertically integrated operation producing finished copper cathode

on-site in Arizona for domestic U.S. supply chains, has an after-tax net present value (8%) of $1.3

billion and an internal rate of return (IRR) of 20.9% at a long-term copper price of $4.10/lb;

 One of the most substantial open pit copper projects in the U.S. with total Measured and

Indicated (“M&I”) Mineral Resources in the open pit of 551 million tons at a total copper grade of

0.35%, capable of supplying 8% of recent annual U.S. domestic copper production1

 Simplified and lower risk path to permitting; the Gunnison Project has current operating permits

and there is a more streamlined amendment process to State and Local permits to proceed with

open pit mining;

 Significant benefits for the community and local economy through the payment of over $840

million in U.S. federal, state, and local taxes, partnerships with local institutions such as Cochise

College, and the creation of over 650 local jobs;

 Average annual copper cathode production of 83,700 tons (167 million lbs) over the first 16

years and total production of 1,355,900 tons (2,712 million lbs) over the entire 18 year mine life

at an average Cash Cost (C1) of $1.42/lb and Sustaining Cash Cost2 of $1.94/lb of copper

produced;

 Total initial capital cost of $1.3 billion and after-tax payback period for initial capital of 4.1 years;

 Environmental advantages include lower water usage per pound of copper produced versus

copper concentrate producers, up to 10% reduced energy consumption due to on-site clean

energy production, and zero risk of environmental impacts from tailings dam failures as there

are no tailings produced.

1 U.S. Geological Survey, Mineral Commodity Summaries, January 2024

2 Sustaining Cash Cost = Cash Cost + Sustaining Capex + Deferred Stripping + Royalties

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Dr. Stephen Twyerould, CEO, commented: “The positive outlook for copper prices, combined with

advancement of sulfide leaching technologies, and the greater overall copper extraction afforded by

open pit mining and heap leaching, has prompted us to focus on an open pit alternative to ISR. We are

very excited by these results, which clearly demonstrate the project is substantial and highly

competitive amongst its peers.”

Craig Hallworth, CFO, commented: “Gunnison Copper, with its newly optimized Gunnison Project and

soon to be producing Johnson Camp Mine, presents an attractive opportunity for investors to gain

leverage to the copper price through a pure play vehicle. Given the portfolio’s location in the Arizona

Copper Belt, the fully permitted status of Johnson Camp and streamlined path to permitting for

Gunnison via permit amendments, we look forward to directly supplying critical U.S. supply chains in

the clean energy, defense, and manufacturing sectors in our expected macro environment of rising

copper prices and producer multiples.”

Roland Goodgame, SVP Business Development, commented: “The future of Gunnison has evolved to

a lower risk open pit option with great economics. The opportunities the Gunnison project presents will

benefit the local community and the greater Arizona economy. Significant direct jobs (over 650) and

indirect jobs will be created in addition to $842 million in revenues to local, state and federal tax. The

historical mining assets in the Cochise Mining District will be leveraged and fully developed to benefit

the local community.”

The PEA is preliminary in nature and includes inferred mineral resources that are considered too

speculative geologically to have the economic considerations applied to them that would enable them to

be categorized as mineral reserves. There is no certainty that the conclusions reached in the PEA will be

realized. Mineral resources that are not mineral reserves do not have demonstrated economic viability.

The PEA was completed by M3 Engineering & Technology Corporation (“M3”) of Tucson, AZ and is

effective as of November 1, 2024. The Technical Report (the “Report”) summarizing the results of the

PEA and prepared in accordance with National Instrument (“NI”) 43-101, will be filed on SEDAR+ and

GCC’s website within 45 days of this news release. The prior technical report on the Gunnison Project

included the Johnson Camp Mine (“JCM”); however, with the new open pit development of the Gunnison

Project and the current construction and upcoming restart of production at JCM in 2025, the Company

will no longer develop the Gunnison Project and JCM using common infrastructure. As a result, an

updated technical report on JCM will be prepared and filed.

Preliminary Economic Assessment Summary

The Project is in Cochise County, Arizona, approximately 65 miles east of Tucson and is held or controlled

100% by GCC. The Gunnison deposit of the Gunnison Project was previously designed and developed

as an in-situ recovery (“ISR”) copper operation. The advancement of sulfide leaching technologies and

the greater copper extraction of open pit mining and heap leaching has prompted GCC to focus on the

open pit alternative to ISR. Nevertheless, the optionality on the fully permitted ISR operations and well

stimulation remains an asset to the Company and this optionality will be maintained. This includes

maintaining full compliance with all regulatory and permit requirements including maintaining hydraulic

control, pumping, monitoring and regulatory reporting.

The Gunnison Open Pit PEA plans to pre-strip alluvial overburden using leased owner-operated

equipment. The deposit is a single large body allowing for more cost effective haulage costs, versus

mining from numerous regional deposits. A primary gyratory crusher will be installed to crush to a P 80 of

6 inches for leaching predominately oxide mineralized materials on the leach pad. A rail spur from the

Union Pacific Southern Pacific (UPSP) will provide straightforward access and inexpensive transportation

for incoming sulfur and outgoing copper cathodes. The sulfuric acid plant will produce acid with a net cost

of approximately $36 a ton and 27 MW of clean energy.

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GCC has a successful track record of permitting and community relations. This, along with the fact that

the Gunnison open pit has no federal permitting nexus, on flat ground with no identified endangered or

threatened species or habitat, and no historical, archaeological, or Native American artefacts, indicates

the Company’s prior permitting track record can be maintained.

Table of Key Metrics

Notes:

1. Hard rock waste includes 85 million short tons of pure limestone, a highly marketable material.

2. Excludes recovery of sulfides from conventional leaching. Some sulfides are expected to leach and provide up-side to

recoveries and copper production.

3. Includes acid plant, leach pad, SX-EW, crushing facility, truck shop, mining pre-strip, highway move, owners’ costs and

other minor infrastructure.

4. Sustaining Capital includes $346 million in deferred stripping costs

5. Cash Cost includes mine operating, crushing and leaching, process plant operating, and general and administrative

costs (“G&A”).

6. Sustaining Cost includes Cash Cost, Sustaining Capex, Deferred Stripping, and Royalties.

7. EBITDA = Revenue – Cash Operating Expenses; Average annual of Y1 to Y16; Revenue includes sales of copper to

U.S. based customers at Spot Price and sales of copper to Triple Flag at Stream Fixed Price (25% of spot)

8. Free Cash Flow = Operating Cash Flow (After Tax) – Capital Expenditures; Average annual of Y1 to Y16

Financial Analysis

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The PEA base case generates an after-tax Net Present Value of approximately $1.3 billion (at a discount

rate of 8%) and an Internal Rate of Return (IRR) of 20.9%. This financial analysis is based on a non-

levered cash flow model, revenues and costs priced in 2024 real US dollars, mid period discounting, and

a valuation date set at the start of Project construction.

Key cash flow model parameters include:

 Copper selling price of $4.10/lb;

 Net copper premium of $0.02/lb (metal premium less freight out);

 Stream deliveries at 25% of market price;

 NSR royalties of 4.5% applies to all copper produced

 State royalty of 5.5% applies to the mineralized material mined from State land (~10% of copper

produced)

 Total copper recovery of approximately 69.5%;

 LoM average of approximately 10.6 pounds of acid consumed for every pound of copper produced

(52 lbs per ton of mineralized material processed);

 Electricity price of $0.079 per Kwh

 Acid plant construction in year -1 with a price of sulfur of $110 per short ton delivered based on

long term price forecast of $75/ton CFR Tampa benchmark plus average direct rail freight in from

Mexican smelters of $35/ton. Including co-generation power credits, the realized price of acid

produced on site averages $36/ton;

 Acid buying price of $150/ton if acid is required above the acid plant’s capacity, and an acid selling

price of $130/ton if excess acid is produced in any specific year;

 Federal income tax rate of 21% and the State income tax rate of 4.9%. State income tax is

deductible for federal income purposes resulting in a combined income tax rate of 24.9%

Table of Capital Costs

The capital cost estimates for this PEA, shown in table below, were developed with a -25% to +30%

accuracy. The Company has used an overall contingency of 20% in accordance with Association of

the Advancement of Cost Engineering International (AACE) Class 5 estimate guidelines.

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Total initial (pre-breakthrough) capital expenditures (including 20% contingency, EPCM, capital spares,

owner’s costs, mobile equipment and freight) are estimated at $1,343 million for initial production of

copper cathode. Mine costs includes pre-stripping and capitalized pre-operating mobile fleet lease costs.

Total sustaining capital costs over the life of the mine are $876 million, which includes deferred stripping,

leach pad expansion and mining equipment.

Facilities at the mine site will include one open pit, two waste stockpiles, primary crushing plant and

conveying system, heap leach pad, Solvent Extraction-Electrowinning (SX-EW) process plant, sulfur

burning sulfuric acid plant with cogeneration capability, technical and operational support offices, mine

truck shop and maintenance buildings, refueling systems, electrical substation and distribution, water

supply and distribution, warehousing and Union Pacific rail spur.

Table of Operating Costs

Mining operating cost estimates, prepared by Independent Mining Consultants (IMC), are based on an

owner’s team managing mining activities, using an owner-operator model. Process operating cost

estimates and G&A cost estimates were prepared by M3, as summarized in the table above (note

numbers may not add due to rounding). Sequencing of operations and annual cash flows are detailed in

Exhibit 1 and 2, at the end of this news release.

The operating site includes numerous infrastructure and location advantages including:

 Union Pacific rail line right next to the property with a 2 km rail spur envisioned.

 High voltage power lines with clean power from SSVEC.

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 Close to local and regional labor pools of Benson, Willcox, and Tucson.

 Flat land conducive for development.

 Deposit is within an enclosed basin; therefore no 404 permit is required.

 No endangered flora or fauna on the property.

Table of Profitability Metrics

Table of Sensitivities

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Mine Plan and Production Profile

Figure 1 shows the stacked total mining profile of waste and process feed. Overall strip ratio is ~2:1,

however 67% of the waste is alluvium gravel which has the advantage of lower mining costs. The

equivalent striping ratio based on hard rock waste mining costs is approximately 1.57:1.

Figure 2 shows the LoM stacked annual copper production by conventional oxide leaching compared to

sulfide leaching. Sulfide leaching makes up only 14% of the total LoM copper production and does not

commence until year 8 of operations.

Mineral Resource Estimate

The mineral resource estimate for the Gunnison Deposit is based on results from 122 drill holes totalling

158,785 feet and is effective as of September 4 th, 2024. Gunnison deposit mineral resources are

classified in order of increasing geological confidence into Inferred, Indicated, and Measured categories

in accordance with the “CIM Definition Standards – For Mineral Resources and Mineral Reserves” and

therefore Canadian National Instrument 43-101. GCC is not aware of any environmental, permitting,

legal, title, taxation, socio-political, marketing or other issues which may materially affect its estimate of

mineral resources.

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The Gunnison deposit mineral resources are reported within an optimized pit at cut-offs that are

reasonable given anticipated open-pit mining methods, processing costs, and economic conditions,

which fulfills regulatory requirements that a mineral resource exists in such form, grade or quality and

quantity that there are reasonable prospects for eventual economic extraction.

The pit-constrained mineral resources are tabulated using an internal cut-off grade of 0.05% TCu. No

mineral resources were estimated within overburden (Tertiary/Quaternary alluvium), and the reported

mineral resources are restricted to lands controlled by GCC.

Total Resources

Resource Class

Short

Tons

(millions)

Total

Cu (%)

Cu

Pounds

(millions)

Measured 191.3 0.37 1,420

Indicated 640.2 0.29 3,684

Measured +

Indicated 831.6 0.31 5,104

Inferred 79.6 0.20 325

Notes:

1. Mineral Resources that are not Mineral Reserves do not have demonstrated economic

viability.

2. Mineral Resources are reported at a 0.05% total copper cut-off grade within an optimized pit.

3. Rounding as required by reporting guidelines, may result in apparent discrepancies between

tons, grade, and contained metal content.

4. The Effective Date of the Mineral Resource estimate is September 4, 2024.

The Gunnison mineral resources were modeled to reflect the detailed lithologic, structural, and oxidation

modeling completed by GCC. Copper mineral domains guided by these geological controls, were

interpreted on east-west vertical cross sections on 100-foot spacing, which encompass the 2.3-mile north-

south and 1.3-mile east-west extents of the deposit. These domains were then used to explicitly constrain

the estimation of copper grades into 50 x 100 x 25-foot (x, y, z) model blocks using 20-foot composites

and inverse-distance interpolation. The grade estimation is further controlled by the incorporation of

search ellipses that reflect the orientations of modeled structural zones, as well as those of favorable

stratigraphic units in areas unaffected by the structures. Sequential copper assay ratios were used to

define three-dimensional surfaces separating the Oxide, Transitional, and Sulfide zones of the

mineralization.

All samples were prepared from manually split half-core sections on-site in Arizona. Split drill core

samples were then sent to Skyline Assayers & Laboratories (“Skyline”) in Tucson, Arizona, an

independent laboratory, for Total Copper (TCu) and Sequential Copper analyses, Acid Soluble Copper

(ASCU) and Cyanide Soluble Cu (CNCu). Skyline is accredited with international standard ISO/IEC

17025:2005 General Requirements for the Competence of Testing and Calibration Laboratories.

Analytical results for (TCu), (ASCu), and (CNCu) were reported. GCC has no relationship with Skyline

Labs other than Skyline being a service provider. Standards, blanks, and duplicate assays are included

at regular intervals in each sample batch submitted from the field as part of an ongoing Quality

Assurance/Quality Control Program.

Mr. Jeffrey Bickel, C.P.G., with the independent firm RESPEC Company LLC (“RESPEC”) of Reno,

Nevada, is a Qualified Person as defined by NI 43-101 and is responsible for this mineral resource

estimate. He has verified, reviewed, and approved the technical disclosure contained in this section of