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Doré Copper Reports High-Grade GOLD Mineralization at Gwillim

Drill Results

PRESS RELEASE

DORÉ COPPER REPORTS HIGH-GRADE GOLD MINERALIZATION AT GWILLIM

Toronto, Ontario – April 21, 2022 – Doré Copper Mining Corp. (the " Corporation" or " Doré Copper")

(TSXV: DCMC; OTCQX: DRCMF; FRA: DCM) announces positive results from two drill holes totaling 819

metres completed in late 2021 on the western part of the Gwillim property, which is under a 50/50 joint

venture with Argonaut Gold Inc. (through its wholly owned subsidiary Prodigy Gold Inc.). Gwillim is located

approximately 8 kilometers by road northwest of Chibougamau, Québec.

Drilling Highlights

KOD-21-02

• 3.33 g/t Au over 13.3 meters, including 26.8 g/t Au over 1.0 metre and 23.2 g/t Au over 0.5 meter

• 3.39 g/t Au over 3.0 meters

• 10.14 g/t Au over 4.0 meters

KOD-21-03

• 3.03 g/t Au over 4.0 meters

• 4.64 g/t Au over 6.0 meters, including 11.69 g/t Au over 2.0 meters

Ernest Mast, President and CEO of Doré Copper, commented, “Today’s results on the Gwillim’s KOD zone

demonstrate good continuity of the mineralization and have extended its depth to 400 meters vertical. We

are in the process of compiling and re-evaluating all the historical data for the Gwillim mine and the KOD

zone. Once completed, we and our JV partner Argonaut Gold Inc. will plan a drilling program to test the

strike and depth extension of both deposits. On our main deliverable for the year, we expect to have t he

results of the preliminary economic assessment (PEA) for our hub-and-spoke operation model by mid-Q2

2022.”

Gwillim Drilling Program

Doré Copper drilled two holes in September 2021 to test the KOD zone, located 300 meters south of the

mined Gwillim Main zone (Figure 1 and Table 1 ). Hole KOD-21-02 intersected three mineralized zones,

including a 13.3 meter zone grading 3.33 g/t starting at a vertical depth of approximately 25 meters and

an intercept of 4.0 meters at 10.14 g/t Au, which is interpreted as the KOD zone. Hole KOD-21-03, drilled

100 meters north-northwest of KOD-21-02, intersected two mineralized zones and demonstrated the

continuity of the KOD zone at depth (Figure 2). The second mineralized zone, 6.0 meters at 4.64 g/t Au

extended the KOD zone vertically by approximately 50 meters from prior historical intercepts (historical drill

holes locations are approximate and will be geore ferenced in the coming months) and is the deepest

intersection to date at a vertical depth of 400 meters.

Gwillim Property

The Gwillim property totals 486 ha. The western part of the property (385 ha) is under a 50/50 joint venture

between Dore Copper and Argonaut Gold Inc. (through its wholly owned subsidiary Prodigy Gold Inc.) with

Dore Copper being the operator. The eastern part of the property (102 ha) is 100% owned by Dore Copper.

Located on the joint venture land, the Gwillim mine operated between 1974 and 1976 and again from 1980

to 1984. In total 254,066 short tons were mined at a grade of 4. 79 g/t Au1. Most of the production came

from the Main zone, which extended along strike for 122 m eters with an average width of 2.6 m eters and

up to a depth of 114 metres.

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In 1987, two high-grade intercepts of 7.0 meters at 33 g/t Au and 7.9 meters at 17.9 g/t Au were drilled by

Greenstone Resources Ltd. at moderate depths of 200 to 300 meters at the KOD zone (300 meters south

of the mined Gwillim Main zone) 2. A further 25 holes were drilled from the surface before a ramp was

developed and the zone was further explored from underground in 1988 but not mined (some development

through ore). In 1989, three more surface holes were drilled to depths of 400 meters with one hole

confirming the extension of the high -grade mineralization beyond 300 m eters vertical depth. An internal

report from 1989 outlined a small historical resource (not NI 43-101 compliant) for the KOD Zone. No other

significant exploration activities are reported after this work.

Gwillim is hosted within the Roy group in the Bruneau Formatio n, in pillowed basalts and gabbroic sill.

Mineralization is hosted predominantly within east -west, steeply dipping structures containing quartz -

carbonate veins with limited amounts of massive sulphides. At KOD, there are two parallel east -west vein

zones, approximately 50 meters apart, with the mineralization predominantly occurring in the northernmost

vein. The thickness of the mineralization varies between 0.3 and 5.0 meters. The KOD zone is open along

strike and downdip to the east under the Gwillim lake.

References:

1 Structural and Stratigraphic Control on Magmatic, Volcanogenic, and Shear Zone-Hosted Mineralization in the

Chapais-Chibougamau Mining Camp, Northeastern Abitibi, Canada – Leclerc et al., 1992 Society of economic geologist

inc. V 107, pp. 963-989.

2 Diamond Drilling Report on the Gwillim Lake KOD Zone, Greenstone Resources (internal report) – Robert McIntosh,

Project Geologist, Flanagan McAdam and Company, December 1989.

Table 1. Gwillim Assays Highlights from the 2021 Drill Program

Hole From

(m)

To

(m)

Width1

(m)

Au

(g/t) Zone

KOD-21-02 28.7 42.0 13.3 3.33 unnamed

including 28.7 29.2 0.5 23.2 unnamed

including 41.0 42.0 1.0 26.8 unnamed

138.5 141.5 3.0 3.39 unnamed

203.5 207.5 4.0 10.14 KOD

KOD-21-03 395.0 399.0 4.0 3.03 unnamed

448.5 454.5 6.0 4.64 KOD

Including 448.5 450.5 2.0 11.69 KOD

1. The true width of the structures intersected is estimated at approximately 55-60% of the downhole width.

Drilling and Quality Control

The Company is using Miiken Drilling as the drilling contractor. Miiken is a joint venture between

Chibougamau Diamond Drilling Ltd., the First Nations community of Ouje-Bougoumou and the First Nations

community of Mistissini both located in the Eeyou Istchee territory.

Sample preparation was done at SGS Canada Inc. in Val -d’Or, Québec, fire assay and ICP analysis was

done at SGS Canada Inc. in Burnaby, B.C. Samples were weighed, dried, crushed to 75% passing 2 mm,

split to 250 g, and pulverized to 85% passing 75 microns. Samples were then fire assayed for Au (50 g)

and sodium peroxide fusion ICP-MS finish for 34 elements.

QA/QC is done in house by Doré Copper Geologists with oversight from the Exploration Manager. The

check samples (blanks and standards – 4% of total samples with another 2% of core duplicates) that were

inserted into the sample batches are verified against their certified values and are deemed a pass if they

are within 3 standard deviations of the certified value. The duplicates are evaluated against each other to

determine mineralization distribution (nugge t). If there are large discrepancies in the check samples, then

the entire batch is requested to be re-assayed.

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Figure 1. Surface plan of a portion of the Gwillim Property showing the location of the 2021 drill holes.

Figure 2. Cross-section of the KOD zone showing holes KOD-21-02 and 03.

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Qualified Person

Andrey Rinta, P.Geo., the Exploration Manager of the Corporation and a "Qualified Person" within the

meaning of National Instrument 43-101, has reviewed and approved the technical information contained in

this news release.

About Doré Copper Mining Corp.

Doré Copper Mining Corp. aims to be the next copper producer in Québec with an initial production target

of +50 Mlbs of copper equivalent annually by implementing a hub-and spoke operation model with multiple

high-grade copper -gold assets feeding its centralized 2,700 tonnes per day mill. The Corporation is

expected to deliver a PEA by mid-Q2 2022 and then initiate a feasibility study and permit applications.

The Corporation has consolidated a large land package in the prolific Lac Doré/Chibougamau and Joe

Mann mining camps that has produced 1.6 billion pounds of copper and 4.4 million ounces of gold 3. The

land package includes 13 former producing mines, deposits and resource target areas within a 60-kilometre

radius of the Corporation’s Copper Rand Mill.

For further information, please contact:

Ernest Mast Laurie Gaborit

President and Chief Executive Officer Vice President, Investor Relations

Phone: (416) 792-2229 Phone: (416) 219-2049

Email: emast@Dorécopper.com Email: lgaborit@Dorécopper.com

Visit: www.dorecopper.com

Facebook: Doré Copper Mining

LinkedIn: Doré Copper Mining Corp.

Twitter: @DoreCopper

Instagram: @DoreCopperMining

3. Sources for historic production figures : Economic Geology, v. 107, pp. 963 –989 - Structural and Stratigraphic Controls on

Magmatic, Volcanogenic, and Shear Zone -Hosted Mineralization in the Chapais -Chibougamau Mining Camp, Northeastern

Abitibi, Canada by François Leclerc et al. (Lac Dore/Chibougamau mining camp) and NI 43-101 Technical Report on the Joe

Mann Property dated January 11, 2016 by Geologica Groupe-Conseil Inc. for Jessie Ressources Inc. (Joe Mann mine).

Cautionary Note Regarding Forward-Looking Statements

This news release includes certain "forward -looking statements" under applicable Canadian securities legislation.

Forward-looking statements include predictions, projections and forecasts and are often, but not always, identified by

the use of words such a s "seek", "anticipate", "believe", "plan", "estimate", "forecast", "expect", "potential", "project",

"target", "schedule", "budget" and "intend" and statements that an event or result "may", "will", "should", "could" or

"might" occur or be achieved and other similar expressions and includes the negatives thereof. Specific forward-looking

statements in this press release include, but are not limited to the Corporation and its JV partner Argonaut Gold Inc.

planning a drilling program to test the strike and depth extension of both deposits; aiming to be the next copper producer

in Québec with an initial production target of +50 Mlbs of copper equivalent annually ; PEA by mid -Q2 2022 ;

implementing a hub-and spoke operation model; and initiating a feasibility study and permit applications after the PEA.

All statements other than statements of historical fact included in this release, including, without limitation, statements

regarding the timing and ability of the Corporation to receive necessary regulatory approvals, and the plans, operations

and prospects of the Corporation and its properties are forward -looking statements. Forward-looking statements are

necessarily based upon a number of estimate s and assumptions that, while considered reasonable, are subject to

known and unknown risks, uncertainties and other factors which may cause actual results and future events to differ

materially from those expressed or implied by such forward-looking statements. Such factors include, but are not limited

to, actual exploration results, changes in project parameters as plans continue to be refined, future metal prices,

availability of capital and financing on acceptable terms, general economic, market or busi ness conditions, uninsured

risks, regulatory changes, delays or inability to receive required regulatory approvals, health emergencies, pandemics

and other exploration or other risks detailed herein and from time to time in the filings made by the Corporat ion with

securities regulators. Although the Corporation has attempted to identify important factors that could cause actual

actions, events or results to differ from those described in forward-looking statements, there may be other factors that

cause such actions, events or results to differ materially from those anticipated. There can be no assurance that such

statements will prove to be accurate, as actual results and future events could differ materially from those anticipated

in such statements. Accord ingly, readers should not place undue reliance on forward -looking statements. The

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Corporation disclaims any intention or obligation to update or revise any forward -looking statements, whether as a

result of new information, future events or otherwise, except as required by law.

Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the

policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this

news release.