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Doré Copper Announces Significant Mineral Resource Increase FOR Corner BAY ̶ Preliminary Economic Assessment Underway

Economic Studies

PRESS RELEASE

DORÉ COPPER ANNOUNCES SIGNIFICANT MINERAL RESOURCE INCREASE

FOR CORNER BAY ̶ PRELIMINARY ECONOMIC ASSESSMENT UNDERWAY

Toronto, Ontario – October 6, 2021 – Doré Copper Mining Corp. (the " Corporation" or "Doré Copper")

(TSXV: DCMC; OTCQ X: DRCMF; FRA: DCM) is pleased to announce an updated and significantly

expanded Mineral Resource Estimate (“MRE”) for its flagship Corner Bay high-grade copper-gold project

located approximately 55 kilometers by road from the Corporation’s Copper Rand mill, near Chibougamau,

Québec.

This significant increase in the size of the MRE at Corner Bay represents an important step-change for the

economic potential of an underground mining operation. This MRE will form the basis of the mine plan to

be outlined in a preliminary economic assessment (“PEA”) anticipated to be completed by January 2022.

Join us at our webinar on Wednesday, October 6 at 12:00 PM EST:

https://us06web.zoom.us/s/84095898479?pwd=eGVPTytxUXl4a2ZwYlBQNi9IQzhFUT09

Highlights of the Corner Bay Updated MRE

• Corner Bay deposit contains an Indicated Resource of 2.66 Mt @ 2.68% Cu and 0.26 g/t Au and

an Inferred Resource of 4.54 Mt @ 3.20% Cu and 0.27 g/t Au

• Contains 157 million pounds of copper in the Indicated category and 320 million pounds of

copper in the Inferred category

• Corner Bay doubles in size from prior 2019 estimate:

o An increase of 140% in total tonnage and 107% in contained copper metal in all resource

categories

• Discovery cost of $0.02 per pound1 since acquisition in 2017

• Excellent continuity of mineralization

• Infrastructure in place:

o Ramp access to a vertical depth of 115 meters and two kilometers of development on three levels

o Within trucking distance of the Corporation’s 2,700 tpd mill

• Significant exploration potential exists to further increase the MRE:

o Ongoing drilling program successfully connecting the Main Vein and Lower Deep Vein (both

below dyke)

o Deposit open down plunge below vertical depth of 1,100 meters

o Subparallel zones untested

• PEA anticipated in January 2022

“When we acquired Corner Bay in 2017 , we saw the opportunity to significantly grow the deposit and

generate value. Our recent drilling success has increased the mineral resource tonnage by 360% since

acquisition and 140% from the 2019 MRE , at a very low discovery cost of $0.02 per pound and with still

significant exploration potential on the property. Corner Bay is now one of the few undeveloped high-grade

copper deposits (+3% Cu) in the world today,” said Ernest Mast, President and CEO of Doré Copper.

“Our next priority is the completion of the PEA study for the re-development plan of a hub-and-spoke

operation model with Corner Bay as the main feed to our centralized mill, supplemented by the Devlin and

Joe Mann deposits. With the significant copper grade and size of this mineral resource, the existing mine,

mill and tailings infrastructure, we anticipate demonstrating very attractive economics for our hub-and spoke

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operation. The plan is to continue exploration drilling from surface at Corner Bay and commence infill drilling

in 2022 for a feasibility study anticipated in early 2023.”

Doré Copper has awarded BBA Inc. (Mont-Saint-Hilaire, Québec) the contract to lead the PEA, which will

include Corner Bay as the main feed to the Copper Rand mill along with Devlin and the former Joe Mann

mine as secondary feed sources to its hub-and-spoke operation model.

The PEA will be using the MRE issued today for Corner Bay and the July 28, 2021 MRE for Joe Mann

(Technical Report filed on September 10, 2021). Doré Copper is currently finalizing a MRE update for the

Devlin copper deposit, located 10 kilometers to the west of Corner Bay on the same property. A NI 43-101

technical report supporting the MREs for the Corner Bay and Devlin deposits will be filed on SEDAR

(www.sedar.com) within 45 days.

Mineral Resource Estimate for Corner Bay

The MRE for the Corner Bay deposit (shown in Table 1 and Figure 1) was completed by SLR Consulting

(Canada) Ltd. (“SLR”), an independent global mining advisory and consulting firm, using available drill hole

data as of September 28, 2021. This MRE is based on a datab ase containing a total of 324 diamond drill

holes totaling 140,105 meters, of which 48 holes totaling 46,633 meters were completed by Doré Copper

from 2017 to 2021 (as of the cut-off date).

The Corner Bay deposit also has local significant silver and molybdenum concentrations which will be

evaluated in the feasibility study. The deposit remains open down plunge and there are several parallel

veins to the east and west that remain to be tested.

Table 1. Corner Bay Mineral Resource Estimate (Effective date of October 1, 2021)

Classification Vein Tonnage

(Mt)

Cu Grade

(%)

Au Grade

(g/t)

Cu Contained

(M lbs)

Au Contained

(k oz)

Indicated Main Vein 1 1.77 2.56 0.27 100 15

Main Vein 2 0.50 2.87 0.27 32 4

Main Below Dike 0.38 2.96 0.21 25 3

Total 2.66 2.68 0.26 157 22

Inferred Main Vein 1 0.35 2.77 0.32 22 4

Main Vein 2 - - - - -

Main Below Dike 3.39 3.09 0.25 231 27

Lower Deep 0.42 5.43 0.44 51 6

West Veins 0.26 1.68 0.16 9..6 1.4

East Vein 0.11 2.91 0.21 7 1

Total 4.54 3.20 0.27 320 39

Notes:

1. The stated Mineral Resources comply with the disclosure requirements of National Instrument 43-101 – Standards

of Disclosure for Mineral Projects ("NI 43 -101") and are classified in accordance with the Canadian Institute of

Mining, Metallurgy and Petroleum's "CIM Definition Standards – For Mineral Resources and Mineral Reserves" (the

“CIM Definition Standards”).

2. Mineral Resources are estimated at a cut-off grade of 1.3% Cu.

3. Mineral Resources are estimated using a long-term copper price of US$3. 75 per pound, metallurgical copper

recovery of 95%, and a US$/C$ exchange rate of 0.75.

4. A minimum mining width of two meters was used.

5. Bulk density for Main Vein 1 and Main Vein 2 above dyke is 3.1 g/cm3, East Vein is 2.90 g/cm3, Main Vein below

dyke and Lower Deep Vein is 3.0 g/cm3, and West Veins WV and WV2 is 2.85 g/cm3 and WV3 is 2.92 g/cm3.

6. Mineral Resources are not Mineral Reserves and do not have demonstrated economic viability.

7. Numbers may not add due to rounding.

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Figure 1. Corner Bay Isometric View Showing the Mineral Resources and Potential for Expansion

Figure 2. Corner Bay Cross Section Showing the Mineralized Structures

Mineral Resource Estimation Methodology

The Corner Bay MRE is based on eight veins, three of which are above the principal d yke, two are below

and three are located on the west side of the deposit. For this estimation, the assays from the mineralized

zones were uncapped for copper, capped at 6 .0 g/t for gold and two meter composites were used, except

for the Main Vein below dyke which used full length composites. The domains were estimated into sub -

blocked models using a three -pass inverse distance squared (ID2) or cubed (ID3) interpolation approach.

A minimum thi ckness of 2 m eters was applied to all veins. Indicated Mineral Resources represent areas

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with drill hole spacing up to approximately 60 meters and Inferred Mineral Resources between 60 meters

and 100 meters, with a copper cut-off grade of 1.3%.

Mineral R esource domains and block modelling work was performed using Leapfrog Geo and Edge

software. In addition to standard historical data and database validation techniques, wireframe and block

model validation procedures including wireframe to block volume confirmation, statistical comparisons with

composite and nearest neighbour estimates, and visual reviews in longitudinal section were performed.

Corner Bay Deposit

The Corner Bay deposit was discovered in 1982 . The property was acquired by Ressources MSV Inc. in

1995 and subsequently merged with Campbell Resources Inc. (“Campbell”). Several exploration drilling

programs were carried out up to 2008. An initial NI 43-101 MRE was prepared in 2006. In 2008, Campbell

initiated an underground bulk sampling program by driving a ramp down to 115 meters below surface and

establishing three levels (55, 75 and 105 m eters). The bulk development sample totaling approximately

36,000 tonnes averaging 2.48% Cu and 0.44 g/t Au was processed at the Copper Rand mill with recoveries

of 94.4% for copper and 81.5% for gold.

Doré Copper, while operating as a private company, completed a drilling program of 14,047 meters in 14

holes (including wedges) in 2017-18 and reported a NI 43-101 MRE in 2019. Subsequent drilling programs

by the Corporation in 2020 and 2021 have successfully expanded the deposit along strike and down plunge.

The Corner Bay property is located on the southern flank of the Lac Dore Complex . An anorthositic

sequence hosts the copper mineralized shear , striking approximately north-south and dipping 70° west ,

which extends from surface down to 1,300 meters vertically (open) and over one kilometer along strike.

The deposit is bisected by the regional Gabbro Isle dyke, a large north -south striking diorite dyke dipping

sub-vertically.

The deposit consists of four main mineralized veins (subparallel Main Vein 1 and Main Vein 2 above the

dyke, Main Vein below the dyke, and Lower Deep Vein) that make up the bulk of the deposit, and four other

parallel smaller veins (West Veins and East Vein) (Figures 1 and 2). The Main Vein below the dyke is the

continuation of the mineralization above in Main Vein 1 and 2, but as the name implies, it is located below

the Gabbro Isle dyke and dips 80° towards the west. The Lower Deep Vein is a deeper lens in the same

shear, with the same general orientation as the other veins, dipping 65° west. The current drilling program

is successfully demonstrating continuity between the Main Vein below the dyke and the Lower Deep Vein

(assays are pending). This part of the deposit has limited strike extension and remains open down plunge.

Identified and drilled in 2020 and 2021, the West Veins are three parallel veins located 60 meters to 100

meters below surface and located approximately 400 meters west of the Main Vein 1 and 2. They are sub-

vertical and range in thickness from 0.5 meter to 3.0 meters. The mineralized structure hosting these veins

extends for hundreds of meters along strike and still remains sparsely drilled. A new parallel vein (East

Vein) was identified 200 meters to the east of the Main Vein above the dyke. Both the West and East Veins

are open along strike and at depth.

In general, the mineralization ranges in thickness from 0.4 meter to over 20 meters ( all eight veins have

been modelled with a two meter minimum true thickness). Mineralization consists mostly of pyrite and

chalcopyrite with sporadic pyrrhotite.

Qualified Persons

The MRE for Corner Bay was prepared by Luke Evans, M.Sc., P.Eng., ing. and Marie-Christine Gosselin,

B.Sc., P.Geo , of SL R, both “Independent Qualified Person s” as defined by NI 43 -101. The Qualified

Persons are not aware of any environmental, permitting, legal, title, taxation, socio -economic, marketing,

political, or other relevant factors that could materially affect the MREs.

Andrey Rinta, P.Geo., the Explo ration 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.

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Town Hall Webinar

Ernest Mast, President and CEO of Doré Copper will discuss the MRE update for Corner Bay, the

Corporation’s key asset for an eventual hub-and-spoke operation, at a webinar on Wednesday, October 6

at 12:00 PM EST.

To participate in the Town Hall Webinar, please register here with your full name:

https://us06web.zoom.us/s/84095898479?pwd=eGVPTytxUXl4a2ZwYlBQNi9IQzhFUT09

About Doré Copper Mining Corp.

Doré Copper Mining Corp. is a copper -gold explorer and developer in the Chibougamau area of Québec,

Canada. The Corporation is focussed on implementing its hub -and-spoke development strategy by

advancing its key high -grade copper-gold brownfield projects t owards a restart of operations. Our goal is

to achieve an annual production of 60 M lbs of copper equivalent (or 100,000 oz gold equivalent).

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

Mann mining ca mps that has produced 1.6 billion pounds of copper and 4.4 million ounces of gold2. The

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

radius of the Company’s 2,700 tpd mill (Copper Rand Mill).

Doré Copper plans to deliver a PEA of its hub -and-spoke model in January 2022. The Corporation is

completing its 2021 drilling program of 50,000 meters on its properties in the Lac Doré and Chibougamau

area of Québec.

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

For more information, please visit: www.dorecopper.com

Facebook: Doré Copper Mining

LinkedIn: Doré Copper Mining Corp.

Twitter: @DoreCopper

Instagram: @DoreCopperMining

1. Non-audited estimation using exploration expenditures from October 2017 up to June 30, 2021 divided by the increase in the total

pounds of copper in mineral resources. Exploration expenditures include drillings costs, assays costs, geophysics, geochemistry, and

a portion of indirect costs such as consultants, maintenance, travel and operations support. This is considered a non -IFRS financial

measure.

2. 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 Doré/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).

Information Concerning Estimates of Mineral Reserves and Resources

The Mineral Reserve and Mineral Resource estimates in this press release have been disclosed in accordance with NI

43-101, which differs significantly from the requirements of the U.S. Securities and Exchange Commission (the “SEC”),

and information with respect to mineralization and Mineral Reserves and Mineral Resources contained herein may not

be comparable to similar information disclosed by U.S. companies. The requirements of NI 43 -101 for identification of

‘‘reserves’’ are not the same as those of the SEC, and reserves reported by the C ompany in compliance with NI 43 -

101 may not qualify as ‘‘reserves’’ under SEC standards. Under U.S. standards, mineralization may not be classified

as a ‘‘reserve’’ unless the determination has been made that the mineralization could be economically and le gally

produced or extracted at the time the reserve determination is made. In addition, and without limiting the generality of

the foregoing, this press release uses the terms ‘‘Measured Resources’’, ‘‘Indicated Resources’’ and ‘‘Inferred

Resources’’. U.S. investors are advised that, while such terms are recognized and required by Canadian securities

laws, the SEC has not recognized them in the past. U.S. investors are cautioned not to assume that any part of a

‘‘Measured Resource’’ or ‘‘Indicated Resource’ ’ will ever be converted into a ‘‘reserve’’. U.S. investors should also

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understand that ‘‘Inferred Resources’’ have a great amount of uncertainty as to their existence and as to their economic

and legal feasibility. It cannot be assumed that all or any part of ‘‘Inferred Resources’’ exist, are economically or legally

mineable or will ever be upgraded to a higher category. Under Canadian securities laws, ‘‘Inferred Resources’’ may not

form the basis of feasibility or pre -feasibility studies except in certain cases. Disclosure of ‘‘contained ounces’’ in a

Mineral Resource is a permitted disclosure under Canadian securities laws, however, the SEC normally only permits

issuers to report mineralization that does not constitute ‘‘reserves’’ by SEC standards as in place tonnage and grade,

without reference to unit measures. Accordingly, information concerning mineral deposits set forth in this press release

may not be comparable with information made public by companies that report in accordance with U.S. standards.

The SEC has adopted amendments to its disclosure rules to modernize the mineral property disclosure requirements

under the U.S. Securities Exchange Act of 1934, as amended (the “Exchange Act”). These amendments became

effective February 25, 2019 (the “SEC Modernization Rules”) with compliance required for the first fiscal year beginning

on or after January 1, 2021. Under the SEC Modernization Rules, the historical property disclosure requirements for

mining registrants included in Industry Guide 7 under the U.S. Securities Act of 1933, as amended, will be rescinded

and replaced with disclosure requirements in subpart 1300 of SEC Regulation S -K. As a result of the adoption of the

SEC Modernization Rules, the SEC now recognizes estimates of “Measured Minera l Resources”, “Indicated Mineral

Resources” and “Inferred Mineral Resources.” In addition, the SEC has amended its definitions of “Proven Mineral

Reserves” and “Probable Mineral Reserves” to be “substantially similar” to the corresponding standards under N I 43-

101. While the SEC will now recognize “Measured Mineral Resources”, “Indicated Mineral Resources” and “Inferred

Mineral Resources”, U.S. investors should not assume that any part or all of the mineralization in these categories will

ever be converted into a higher category of Mineral Resources or into Mineral Reserves. Mineralization described using

these terms has a greater amount of uncertainty as to its existence and feasibility than mineralization that has been

characterized as reserves. Accordingl y, U.S. investors are cautioned not to assume that any Measured Mineral

Resources, Indicated Mineral Resources, or Inferred Mineral Resources that the Company reports are or will be

economically or legally mineable. Further, “Inferred Mineral Resources” have a greater amount of uncertainty as to their

existence and as to whether they can be mined legally or economically. Therefore, U.S. investors are also cautioned

not to assume that all or any part of the “Inferred Mineral Resources” exist. There is no ass urance that any Mineral

Reserves or Mineral Resources that the Company may report as “Proven Mineral Reserves”, “Probable Mineral

Reserves”, “Measured Mineral Resources”, “Indicated Mineral Resources” and “Inferred Mineral Resources” under NI

43-101 would be the same had the Company prepared the reserve or resource estimates under the standards adopted

under the SEC Modernization Rules.

Mineral Resources are not Mineral Reserves, and do not have demonstrated economic viability, but do have reasonable

prospects for economic extraction. Measured and Indicated Mineral Resources are sufficiently well defined to allow

geological and grade cont inuity to be reasonably assumed and permit the application of technical and economic

parameters in assessing the economic viability of the Mineral Resource. Inferred Mineral Resources are estimated on

limited information not sufficient to verify geological and grade continuity or to allow technical and economic parameters

to be applied. Inferred Mineral Resources are too speculative geologically to have economic considerations applied to

them to enable them to be categorized as Mineral Reserves. There is no certainty that Mineral Resources of any

classification can be upgraded to Mineral Reserves through continued exploration.

Cautionary Note Regarding Forward-Looking Statements

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

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

the use of words such as "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 significant increase in the size of the MRE at Corner

Bay representing an important step-change for the economic potential of an underground mining operation, PEA to be

completed by January 2022, significant exploration potential to further increase the MRE, demonstrating very attractive

economics for our hub -and spoke opera tion, plan to continue exploration drilling from surface at Corner Bay and

commence infill drilling in 2022, feasibility study anticipated in early 2023, implementing a hub-and-spoke development

strategy by advancing the Corporation’s key high-grade copper-gold brownfield projects towards a restart of operations,

and the Corporation’s goal of achieving an annual production of 60 M lbs of copper equivalent (or 100,000 oz gold

equivalent).

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 estimates and assumptions that, while considered reasonable, are subject to

known and unknown risks, uncertainties an d 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 parameter s as plans continue to be refined, future metal prices,

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

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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 Corporation with

securities regulators. Although the Corporation has attempted to identify important factors that cou ld 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. Accordingly, readers should not place undue reliance on forward -looking statements. The

Corporation disclaims any i ntention 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 def ined in the

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

news release.