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Doré Copper Intersects 14.2% Copper, 1.16 G/T GOLD and 28.0 G/T Silver over 1.5 Meters at Cedar BAY and Intersects High-Grade Vein IN Crown Pillar at Copper Cliff

Drill Results

PRESS RELEASE

DORÉ COPPER INTERSECTS 14.2% COPPER, 1.16 G/T GOLD AND 28.0 G/T SILVER

OVER 1.5 METERS AT CEDAR BAY AND INTERSECTS HIGH-GRADE VEIN IN

CROWN PILLAR AT COPPER CLIFF

Toronto, Ontario – August 5, 2020 – Doré Copper Mining Corp. (the "Company" or "Doré Copper")

(TSXV: DCMC) is pleased to announce results from its ongoing 2020 drill program at the Cedar Bay deposit.

These results show the extension of the Cedar Bay Central Vein and has identified new targets in

Zone 21 and the Crown Pillar of the adjacent Copper Cliff mine. The Cedar Bay program is focused on

testing the lateral extension of the 10-20 and Central veins and the vertical extension of the Main vein.

Ongoing drilling is testing the down-dip extension of historical intercepts on the 10-20A and 10-20B veins

and the Main vein below the lowest historic mine workings.

Drilling Highlights (refer to Table 1):

• CDR-20-04CB - Central Vein: 1.5 meters of 14.2% copper (Cu), 1.16 g/t gold (Au) and 28.0 g/t

silver (Ag) (TW approx. 1.2 meters) approximately 160 meters down dip and along strike

from hole CB-27-9 that intercepted 2.0 meters (TW) of 15.2 g/t Au and 4.8% Cu.

• CDR-20-07 - Zone 21_1: 2.25 meters of 4.9% Cu, 0.46 g/t Au and 8.6 g/t Ag (TW of approx.

1.3 meters).

• Four intercepts in the crown pillar of the adjacent Copper Cliff Mine, including CDR-20-04B

intersecting 2.3 meters (TW) of 7.3% Cu, 13.6 g/t Au and 38.4 g/t Ag, with the four intercepts

averaging 5.0 meters of 3.65% Cu, 5.31 g/t Au and 20.5 g/t Ag (TW of approx. 2.2 meters)

between two intercept areas.

Ernest Mast, President and CEO of Doré Copper Mining Corp. stated, “The latest intercepts at Cedar Bay

support the expansion of mineralization in the Central zone with the highest-grade copper intercept received

to date. The identification of a potential expansion of Zone 21 and the presence of high-grade veins in the

Crown Pillar of the Copper Cliff mine further highlight the upside of this deposit. The results continue to

support the eventual hub-and-spoke restart of the camp along with the Corner Bay and Joe Mann deposits

using our existing 2,700 tpd mill as a central processing facility.”

Cedar Bay Drill Program

Cedar Bay Property

The Cedar Bay property is located five kilometers by road from the Company’s Copper Rand Mill that

operated from 1959 to 1990 producing 3,900,000 tonnes grading 1.63% Cu and 3.21 g/t Au. The deposit

comprises multiple parallel to sub-parallel, NW-SE striking, steeply dipping extensional shears which are

mineralized with semi-massive to massive sulfides (Cpy +/- Py +/- Po). All deposits along the Lac Doré

complex share the same general attributes. At Cedar Bay there are currently 5 identified parallel zones –

Main 1&2, Central, 10_20 A&B (from SW to NE) as well as several other smaller lenses in between.

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A plan view is shown in Figure 1 below.

Figure 1. 2018 drilling as well as hole CDR-20-08A was done from the west and the 2020 directional program

as well as the follow up hole beneath Zone 21 was done from the East/North side of the deposit.

Cedar Bay has 130,000 tonnes of estimated indicated resources grading 9.44 g/t Au and 1.55% Cu and

230,000 tonnes of inferred resources grading 8.32 g/t Au and 2.13% Cu, all located in the 10-20A, 10-20B

and Central structures (In the 2019 43-101 technical report all resources are reported on a minimum 2 m

vein width). In addition, at the time of mine closure there are historical resources of 250,000 tonnes grading

5.5 g/t Au and 0.97% Cu in the main vein and 10-20 structures immediately below the deepest mining level

of 670 meters (the mine shaft extends to 1036 meters).

Central, Main and 10-20A and 10-20B veins

Holes CDR 20-04 and 20-05 were drilled from the Copper Cliff property to intersect the parallel mineralized

structures at Cedar Bay employing directional drilling technology. The holes were drilled to test the strike

extensions of the resources defined in 2019. Both holes were initiated with a dip of -60 degrees and then

were corrected using Aziwell directional drilling to -19 degrees, -35 degrees (for the two cut-offs on hole

4C) and -38 degrees on hole 5. A third cut was prepared on hole CDR-20-04C and will be drilled once

contractor travel can be arranged in the very near future. The holes are targeting mineralization in the Main

veins, Central vein and 10-20 veins that are adjacent to the existing shaft (see figure 2 below).

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Figure 2. Section view showing the drill traces of the directional holes drilled from Copper Cliff (NE). Yellow

trace depicts the pilot hole and cut-offs for hole 4C, blue depicts the trace for hole 5. In bright red are the

10_20A&B veins and the Central vein within which the 2018 resources are contained. The pale red consists of

the projected Main zone veins.

The program initiated in early March and was stopped on March 24th due to the COVID-19 measures

announced by the Québec government. The program was reinitiated on May 14th and the Company and its

contractors implemented protocols to ensure best health practices and communicating these to local

stakeholders. After completing the preparation of the third cut on hole CDR-20-04C, the directional drilling

crew finished their shift and a replacement group of technicians was not available therefore the down-dip

follow-up of hole CDR-20-04CB will be tested at a later date. Drilling is currently testing the down dip from

holes CDR-18-02W2 that intercepted 2.4 meters grading 4.54% Cu and 15.4 g/t Au and CDR-18-03 that

intercepted 2.4 meters of 1.67% Cu and 19.5 g/t Au on 10-20 A and 3.3 meters grading 5.1 g/t Au and 1.4%

Cu on the Central vein.

Each hole crossed the host structure of the mineralized veins, however, only two of the intercepts on the

Central vein, Main vein and 10-20A and 10-20B hit economic-grade mineralization and are highlighted in

Table 1. The high-grade copper intercept on hole CDR-20-04CB, 14.2% Cu and 1.16 g/t Au over 1.5

meters is located approximately 160 meters down dip and along strike from hole CB-27-9 that intercepted

over a two meter true width, 4.8% Cu and 15.2 g/t Au. The high-grade Central vein remains open down dip

and along strike to the north-west. Hole CDR-18-08A and a wedge currently underway will test the area

between the two intercepts on the central vein as well as the down-dip extensions of the 10-20 A and B

veins. Typically, ore within the Lac Doré complex exhibits a steep plunge. The current drilling will help better

characterize the behaviour and plunge of the ore shoots of the Central, 10-20 A and 10-B structures. The

intercept on the Main vein, CDR-20-04CB of 2.0 meters grading 2.87 g/t Au and 0.3% Cu is located 160

meters down dip of historic intercept CB-27-3 that intersected 5.8 meters of 2.0 g/t Au and 0.4% Cu. CDR-

20-05 was testing the 10-20, Central and Main veins 100 m along strike towards a fault which terminates

the mineralization to the SE.

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Zone 21

Zone 21 occurs as the north-easternmost vein at Cedar Bay or south-westernmost at Copper Cliff and was

mined over the historic Copper Cliff and Cedar Bay claims. The zone mined had a strike of 150-200 meters

and a vertical extent of 400 m (490 m from surface). The western half of the mineralized zone is on Doré

Copper land. Hole CDR-20-07 targeted the down-dip extension of the ore body on its west side

approximately 40 meters beneath the lowest mining level and intersected 2.25 meters grading 4.9% Cu,

0.46 g/t Au and 8.6 g/t Ag. Twenty-two meters downhole was the intercept of a secondary parallel vein of

2.1 meters grading 2.4% Cu, 0.34 g/t Au, and 8.4 g/t Ag. The deposit remains open down dip and along

strike at this level. Hole CDR-20-06 tested Zone 21 approximately 100 meters along strike to the NW of

previous mining areas at a depth of 300 meters and did not intersect mineralization.

Copper Cliff Crown Pillar

The Copper Cliff crown pillar is 85 m in height down dip according to historic sections and plans with the

first development level being that depth below the surface. In the course of our 2020 program at Cedar Bay,

the drill holes were collared at Copper Cliff and drilled SW. Near surface the crown pillar was intersected

by 3 of the holes with high-grade Cu and Au mineralization in hole CDR-20-04 (C & CB) and a lower-grade

intercept in hole CDR-20-05. Historic drilling crossed more than 4 zones near surface. Further drill testing

needs to be completed along strike and from the surface to 85 m as they may provide near-surface potential

resources.

Table 1 – Selected drill intercepts from drilling at Cedar Bay as part of the 2020 drill program

Hole Structure From

(m)

To

(m)

Depth

(vertical

m)

True

width

(m)

Cu

(%)

Au

(g/t)

Ag

(g/t)

CDR-20-04C Central 1430.65 1435.05 1077 4.0 0.5 1.0 1.5

CDR 20- 04CB Central 1554.9 1556.4 1241 1.2 14.2 1.16 28

CDR 20-04CB Main 1593.7 1597.0 1267 2.0 0.3 2.87 4.2

CDR 20-07 Zone 21_1 600 602.25 530 1.3 4.9 0.46 8.6

CDR 20-07 Zone 21_2 633.85 636 560 1.2 2.4 0.34 8.9

CDR-20-04B Copper Cliff

Crown Pillar 32.7 38 34 2.3 7.3 13.6 38

CDR-20-04C Copper Cliff

Crown Pillar 34.5 39.5 35 2.2 5.8 7.7 36

CDR-20-04 Copper Cliff

Crown Pillar 36 40.8 36 2.1 4.9 7.3 25

CDR-20-05 Copper Cliff

Crown Pillar 31 36 34 2.2 1.3 1.1 7.8

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 and assays were done at SGS lab in Val-d’Or, Québec. Samples were weighed, dried,

crushed to 75% passing 2 mm, split 250 g, pulverized to 85% passing 75 microns. Samples were then fire

assayed for Au (30 g) and sodium peroxide fusion ICP-MS finish for 34 elements.

QA/QC is done in house by Dore 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 3sd of the certified value. The duplicates are evaluated against each other to determine

mineralization distribution (nugget). If there are large discrepancies in the check samples, then the entire

batch is requested to be re-assayed.

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The historical drilling results disclosed in this news release about Corner Bay and Cedar Bay was taken

from the technical report entitled “Technical Report on the Corner Bay and Cedar Bay Projects, Northwest

Québec, Canada” dated June 15, 2019, prepared by Luke Evans, M.Sc., P.Eng., which is available under

Doré Copper's profile on SEDAR at www.sedar.com.

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 is engaged in the acquisition, exploration and evaluation of mineral properties. Doré Copper

completed a qualifying transaction on December 13, 2019, establishing itself as a copper-gold explorer and

developer in the Chibougamau area of Québec, Canada. Doré Copper, through its wholly owned subsidiary

CBAY Minerals Inc., holds a 100% interest in the exploration-stage Corner Bay project and the exploration-

stage Cedar Bay project, both located in the vicinity of Chibougamau, Québec, as well as the 2,700-tonne-

per-day Copper Rand processing mill. Doré Copper has an option agreement to acquire 100% of the Joe

Mann property (see press release dated January 2, 2020), whereby if certain payments and spending

requirements are met over a three-year period, the Company will become the 100% owner of the 1,990-

hectare property.

For further information regarding Doré Copper, please visit the Company’s website at www.dorecopper.com

or refer to Doré Copper’s SEDAR filings at www.sedar.com.

For further information, please contact:

Ernest Mast

President and Chief Executive Officer

Phone: (416) 792-2229

Email: [email protected]

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 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. All statements other than statements of historical fact included in this

release, including, without limitation, statements regarding the timing and ability of the Company to receive

necessary regulatory approvals, and the plans, operations and prospects of the Company 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 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 business

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 Company with securities regulators. Although the Company 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 assu rance 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

Company 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.