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Alamos Gold Continues to Extend High-Grade Gold Mineralization at Island Gold, Including within Hanging Wall and Footwall Zones in Proximity to Existing Infrastructure

Drill Results

ALAMOS GOLD INC.

Brookfield Place, 181 Bay Street, Suite 3910, P.O. Box #823

Toronto, Ontario, Canada M5J 2T3

Telephone: (416) 368-9932 or 1 (866) 788-8801

All amounts are in United States dollars, unless otherwise stated.

F O R I M M E D I A T E R E L E A S E

W E B S I T E : w w w . a l a m o s g o l d . c o m T R A D I N G S Y M B O L : T S X : A G I N Y S E : A G I

Alamos Gold Continues to Extend High-Grade Gold Mineralization at Island Gold,

Including within Hanging Wall and Footwall Zones in Proximity to Existing

Infrastructure

Toronto, Ontario (June 15, 2023) – Alamos Gold Inc. (TSX:AGI; NYSE:AGI) (“Alamos” or the

“Company”) today reported new results from underground exploration drilling at the Island Gold

mine, further extending high-grade gold mineralization across the Island Gold Deposit . This

included multiple significant high -grade intercepts within several recently defined hanging wall

and footwall structures in proximity to existing underground infrastructure. All reported drill widths

are true width of the mineralized zones, unless otherwise stated.

• Island West: high-grade mineralization exte nded outside of Mineral Reserves and

Resources within the main C-Zone. The C and E1E-Zones are the main structures which

host the majority of currently defined Mineral Reserves and Resources at Island Gold.

New highlights include:

• 146.33 g/t Au (37.19 g/t cut) over 2.20 m (580-473-22); and

• 38.92 g/t Au (38.92 g/t cut) over 2.10 m (790-479-16).

• Island West Hanging Wall Zones: high-grade gold mineralization intersected within sub-

parallel zones in the hanging wall, and within a newly defined perpendicular structure,

the “NS1” Zone. Multiple sub-parallel and perpendicular hanging wall zones have been

defined o ver the past year in proximity of existing underground infrastructure and

represent a significant opportunity to add near mine Mineral Reserves and Resources.

New highlights include:

NS1 Zone

• 89.31 g/t Au (7.73 g/t cut) over 2.40 m (770-466-03);

• 25.57 g/t Au (5.68 g/t cut) over 2.50 m (770-466-07);

• 42.27 g/t Au (7.43 g/t cut) over 2.30 m (580-473-26);

• 16.06 g/t Au (6.95 g/t cut) over 2.80 m (770-466-02); and

• 14.50 g/t Au (10.08 g/t cut) over 3.10 m (580-473-25).

G1 Zone

• 60.03 g/t Au (25.70 g/t cut) over 2.50 m (790-479-13); and

• 11.13 g/t Au (6.82 g/t cut) over 2.20 m (850-471-01B).

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• Island West Footwall Zones : high-grade gold mineralization intersected within newly

defined sub-parallel structure the “DN” zone. New highlight includes:

• 22.34 g/t Au (22.34 g/t cut) over 2.90 m (790-479-04).

• Island East: high-grade mineralization extended outside of Mineral Reserves and

Resources in the main E1E-Zone. New highlights include:

• 104.48 g/t Au (50.76 g/t cut) over 3.10 m (840-608-49);

• 40.54 g/t Au (33.33 g/t cut) over 2.50 m (840-608-43); and

• 11.93 g/t Au (11.93 g/t cut) over 4.20 m (840-632-17).

• Island East Footwall Zones : high -grade gold mineralization intersected within sub-

parallel zones in the footwall (NTH2, NTH3) in proximity to existing underground

infrastructure. New highlights include:

NTH2 Zone

• 44.48 g/t Au (9.71 g/t cut) over 3.10 m (620-629-03); and

• 17.91 g/t Au (5.34 g/t cut) over 2.10 m (620-629-01).

NTH3 Zone

• 12.34 g/t Au (7.65 g/t cut) over 3.30 m (840-554-44);

• 16.86 g/t Au (11.40 g/t cut) over 2.30 m (840-554-60);

• 13.21 g/t Au (13.21 g/t cut) over 2.70 m (840-554-04); and

• 11.02 g/t Au (7.29 g/t cut) over 2.30 m (840-566-08).

Note: Drillhole composite intervals reported as “cut” may include higher grade samples which have been cut to: C-zone

@ 225 g/t Au; E1E Zone @ 185 g/t Au. B Zone @ 90 g/t Au; D1 and G1 Zones @ 45 g/t Au; G Zone @ 70 g/t Au; E1D

@ 80g/t Au; DN, NS1, NTH1, NTH2, NTH3 @ 35 g/t Au .

“Our continued exploration success within recently defined sub -parallel structures demonstrate

the significant opportunities to add high -grade ounces near our existing mining horizons. This

includes the newly defined NS1-Zone in the hanging wall which we are currently developing and

mining beyond existing Mineral Reserves and Resources and outside of our 2023 mine plan. We

are also continuing to extend high-grade mineralization across the main Island Gold zone to the

East and West as part of our successful transition from surface exploration drilling to more cost-

effective underground drilling where we leverage our existing development ,” said John A.

McCluskey, President and Chief Executive Officer.

“We expect this ongoing success in both the main zone and subparallel structures to drive further

growth in high -grade near-mine Mineral Reserves and Resources . Given th eir proximity to our

existing underground infrastructure , these ounces will be low-cost to develop and produce ,

highlighting the significant ongoing upside to Phase 3+ Expansion study outlined in 2022 ,” Mr.

McCluskey added.

New highlight intercepts can be found in Table 1, and in Figures 1 to 3 at the end of this news

release.

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2023 Exploration Drilling Program – Island Gold Mine

A total of $14 million is budgeted for exploration at Island Gold in 2023. For the past several years,

the exploration focus has been on adding high-grade Mineral Resources at depth in advance of

the Phase 3+ Expansion study, primarily through surface directional drilling. This exploration

strategy has been successful in tripling the Mineral Reserve and Resource base since 2017. With

a 17-year mine life, and with work on the expansion ramping up, the focus has shifted to a more

cost-effective expanded underground exploration drilling program that will leverage existing

underground infrastructure. This drilling is much lower cost on a per metre basis, is less technically

challenging, and requires significantly fewer metres per exploration target.

The underground exploration drilling program has been expanded from 27,500 metres (“m”) in

2022 to 45,000 m in 2023. The program is focus ed on defining new Mineral Reserves and

Resources in proximity to existing production horizons and infrastructure including along strike,

and in the hanging-wall and footwall. These potential high-grade Mineral Reserve and Resource

additions would be low cost to develop and could be incorporated into the mine plan and mined

within the next several years, further increasing the value of the operation. To support the

underground exploration drilling program, 444 m of underground exploration drift development is

planned to extend drill platforms on the 490, 790, 945, and 980 -levels. In addition to the

exploration budget, 36,000 m of underground delineation drilling has been planned and included

in sustaining capital for Island Gold. A total of 20,027 m of underground exploration drilling, and

6,426 m of delineation drilling has been completed as of June 1, 2023.

A regional exploration program including a total of 7,500 m of drilling is also underway. The focus

will be on evaluating and advancing explor ation targets outside the Island Gold Deposit on the

newly expanded 55,300-hectare Island Gold property.

Island West

Underground Exploration Drilling

Underground drilling from the 580-level and the 790-level exploration drifts continue to extend

high-grade gold mineralization along strike to the west of Mineral Reserves and Resources in the

middle portion of Island West (between vertical depths of 700 m and 1,100 m).

New highlights include (Figure 1, Table 1):

C-Zone:

• 146.33 g/t Au (37.19 g/t cut) over 2.20 m (580-473-22); and

• 38.92 g/t Au (38.92 g/t cut) over 2.10 m (790-479-16).

Island West Hanging Wall Zones

In addition to testing the C-Zone, underground exploration drilling continued to target and expand

on previous drilling that intersected high-grade gold mineralization in sub-parallel structures in the

hanging wall from the 580, 770, 790, and 850 -levels. Additional drilling has been successful in

establishing continuity and extending high -grade gold mineralization within multiple structures

referred to as the B, G, and G1 Zones (Table 1). These zones are located 20 m, 75 m, and 110

m south of the main C-Zone, respectively.

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NS1 Hanging Wall Zone

In addition to the sub-parallel structures, a north -striking structure , NS1, with a high-angle

orientation relative to the C-Zone was identified this year. Drill testing, and subsequent exploration

sills along this structure have demonstrated continuity, both along strike, and down -dip. In

addition, other north-striking high-angle structures have been identified across the deposit, which

will be evaluated further as underground exploration drilling advances.

Three exploration s ills have been completed along the NS1 structure from the 750, 770, 810 -

levels. A fourth sill is near completion from the 790-level. The objective of these exploration sills

is to demonstrate the continuity of the structure, and high -grade gold mineralization, both along

strike, and from level-to-level down dip. Thus far, the sills have demonstrated excellent continuity,

over a 60 m strike extent to the south, and over 60 m vertically. A highlight from the NS1 zone sill

development was 3,130 tonnes of material mined from the 770-level NS1 sill that graded 15.20

g/t Au. This sill development material and the NS1 zone is beyond currently defined Mineral

Reserves and Resources and outside of the 2023 mine plan.

This further highlights the potential to add high -grade Mineral Re serves and Resources in

proximity of existing production horizons and infrastructure which could be incorporated into the

mine plan and mined within the next several years. These potential high-grade Mineral Reserves

and Resource additions would be low cost to develop, further increasing the value of the operation

and strong economics of the expansion.

New highlights from the Island West Hanging Wall zones include (Figure 2, Table 1):

NS1 Zone

• 89.31 g/t Au (7.73 cut) over 2.40 m (770-466-03);

• 25.57 g/t Au (5.68 g/t cut) over 2.50 m (770-466-07);

• 42.27 g/t Au (7.43 g/t cut) over 2.30 m (580-473-26);

• 16.06 g/t Au (6.95 g/t cut) over 2.80 m (770-466-02); and

• 14.50 g/t Au (10.08 g/t cut) over 3.10 m (580-473-25).

G1 Zone

• 60.03 g/t Au (25.70 g/t cut) over 2.50 m (790-479-13); and

• 11.13 g/t Au (6.82 g/t cut) over 2.20 m (850-471-01B).

Island West Footwall Zone

In addition to testing the C-Zone and the hanging wall zones in Island West, underground

exploration drilling also targeted and expanded on previous drilling that intersected high -grade

gold mineralization within a sub-parallel structure in the footwall from the 790-level. This additional

drilling has been successful in establishing continuity and extending high -grade gold

mineralization within the DN structure. (Figure 2, Table 1). This zone is located 100 m north of the

main C-Zone.

New highlight from the Island West Footwall zone includes:

DN Zone

• 22.34 g/t Au (22.34 g/t cut) over 2.90 m (790-479-04).

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Island East

Underground Exploration Drilling

Underground drilling from the 620 and 840-level exploration drifts continues to extend high-

grade gold mineralization along strike to the east of Mineral Reserves and Resources in the

middle portion of Island East (between vertical depths of 500 m and 1,000 m).

New highlights in the E1E-Zone include (Figure 1, Table 1):

• 104.48 g/t Au (50.76 g/t cut) over 3.10 m (840-608-49);

• 40.54 g/t Au (33.33 g/t cut) over 2.50 m (840-608-43); and

• 11.93 g/t Au (11.93 g/t cut) over 4.20 m (840-632-17).

Island East Footwall Zones

In addition to testing the E1E-Zone, underground exploration drilling continued to target and

expand on previous drilling that intersected high -grade gold mineralization in sub -parallel

structures in the footwall from the 620 and 840-levels. This additional drilling has been successful

in establishing continuity and extending high-grade gold mineralization within multiple structures

referred to as the NTH, NTH2, and NTH3 zones (Figure 3, Table 1). These zones are located 40

m, 90 m, and 75 m north of the main E1E-Zone, respectively.

New highlights from the Island East Footwall zones include (Figure 3, Table 1):

NTH2 Zone

• 44.48 g/t Au (9.71 g/t cut) over 3.10 m (620-629-03); and

• 17.91 g/t Au (5.34 g/t cut) over 2.10 m (620-629-01).

NTH3 Zone

• 12.34 g/t Au (7.65 g/t cut) over 3.30 m (840-554-44);

• 16.86 g/t Au (11.40 g/t cut) over 2.30 m (840-554-60);

• 13.21 g/t Au (13.21 g/t cut) over 2.70 m (840-554-04); and

• 11.02 g/t Au (7.29 g/t cut) over 2.30 m (840-566-08).

In addition to the hanging and footwall zones in Island West, these footwall zones in Island East

further highlight the potential to add high-grade Mineral Reserves and Resources in proximity of

existing production horizons and infrastructure which could be incorporated into the mine plan and

mined within the next several years. These potential high-grade Mineral Reserves and Resource

additions would be low cost to develop, further increasing the value of the operation.

Other Zones

The majority of Island Gold’s Mineral Reserves and Resources and main production horizons are

hosted in the C/E1E structure. The Island Gold Deposit also consists of several sub-parallel and

high-angle mineralized structures outside of the main C/E1E-Zone. As underground development

advances, these sub-parallel hanging wall and footwall structures can be targeted with step-out

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drilling from underground drill platforms. As demonstrated with the newly defined NTH2, NTH3,

and perpendicular NS1 Zone, as well as the B, G, and G1 Zones that were defined in 2022, these

zones have the potential to be converted into new Mineral Reserves and Resources adjacent to

existing underground infrastructure through additional drilling.

Step-out underground exploration drillin g targeting these zones can be completed once

underground development has been established. This drilling allows for the confirmation of the

geometry and potential continuity of mineralization with the objective of defining new Mineral

Resources. These hanging wall and footwall exploration opportunities provide potential further

upside to define additional Mineral Reserves and Resources outside of the main C/E1E -Zone in

proximity to underground development, which would enhance the ounce per vertical metre profile,

and provide multiple mining horizons from the same lateral development levels.

The following are highlights of new hanging wall and footwall intersections from underground

exploration drilling where the geometry and continuity is not yet established (“Unknown Zone”)

(reported composite intervals are uncut and core length) (Table 1):

Footwall Intersections:

• 137.20 g/t Au over 4.70 m (945-624-03);

• 18.39 g/t Au over 4.20 m (945-624-06);

• 25.85 g/t Au over 2.80 m (790-479-11);

• 6.31 g/t Au over 9.80 m (790-479-10); and

• 11.81 g/t Au over 2.70 m (790-479-02).

Hanging Wall Intersections:

• 55.29 g/t Au over 3.70 m (790-479-16);

• 54.79 g/t Au over 2.70 m (850-471-04);

• 47.61 g/t Au over 2.60 m (850-471-02);

• 18.57 g/t Au over 5.90 m (850-471-17);

• 17.48 g/t Au over 3.20 m (790-479-14); and

• 21.04 g/t Au over 2.60 m (850-471-03).

Qualified Persons

Scott R.G. Parsons, P.Geo., FAusIMM, Alamos Gold’s Vice President, Exploration, has reviewed

and approved the scientific and technical information contained in this news release. Scott R.G.

Parsons is a “Qualified Person” as defined by Canadian Securities Administrators’ National

Instrument 43-101 - Standards of Disclosure for Mineral Projects.

Exploration programs at the Island Gold Mine are directed and supervised by Tyler Poulin ,

P.Geo., Chief Geologist at the Island Gold Mine. Tyler Poulin is a “Qualified Person” as defined

by Canadian Securities Administrators’ National Instrument 43-101 - Standards of Disclosure for

Mineral Projects.

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Quality Assurance and Quality Control

Alamos Gold maintains an internal Quality Assurance / Quality Control (QA/QC) program at the

Island Gold Mine to ensure sampling and analysis of all exploration work is conducted in

accordance with best practices.

Access to the Island Gold Mine is controlled by security personnel. Drill core is logged and

sampled at the core logging facility within the mine site under the supervision of a Qualified

Geologist. A geologist marks the individual sample s for analysis, and sample intervals, sample

numbers, standards and blanks are entered into the database. The core is cut in half using an

electric core saw equipped with a diamond tipped blade. One half of the core is placed into a

plastic sample bag and sealed with zip ties in preparation for shipment. The other half of the core

is returned to the core box and retained for future reference. The samples are placed in large

heavy-duty nylon reinforced Fabrene bags, which are identified and sealed before b eing placed

on pallets. The core samples are picked up at the mine site and delivered to AGAT laboratory in

Thunder Bay, Ontario.

Gold is analyzed by a 50 grams fire assay with an Atomic Absorption (AA) finish. Samples greater

than 10.0 g/t Au are re-analyzed using gravimetric finish methods. AGAT is a certified laboratory

and has internal quality control (“QC”) programs that include insertion of reagent blanks, reference

materials, and pulp duplicates.

The Corporation inserts QC samples (blanks and reference materials) at regular intervals to

monitor laboratory performance. Cross check assays are completed on a regular basis in a

secondary accredited laboratory. The QA/QC procedures are more completely described in the

Technical Report filed on SEDAR August 29, 2022.

About Alamos

Alamos is a Canadian -based intermediate gold producer with diversified production from three

operating mines in North America . This includes the Young-Davidson and Island Gold mines in

northern Ontario, Canada and the Mula tos mine in Sonora State, Mexico. Additionally, the

Company has a strong portfolio of growth projects, including the Phase 3+ Expansion at Island

Gold, and the Lynn Lake project in Manitoba, Canada. Alamos employs more than 1,900 people

and is committed to the highest standards of sustainable development. The Company’s shares

are traded on the TSX and NYSE under the symbol “AGI”.

FOR FURTHER INFORMATION, PLEASE CONTACT:

Scott K. Parsons

Senior Vice President, Investor Relations

(416) 368-9932 x 5439

The TSX and NYSE have not reviewed and do not accept responsibility for the adequacy or accuracy of this release.

Cautionary Note

This news release includes certain statements that constitute forward -looking information within the meaning of

applicable Canadian and U.S. securities laws ("forward-looking statements"). All statements in this news release other

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than statements of histor ical fact, which address events, results, outcomes or developments that Alamos expects to

occur are forward-looking statements. Forward-looking statements are generally, but not always, identified by the use

of forward -looking terminology such as "expect", "plan", "estimate", “target”, “budget”, “prospective” “potential”,

“opportunity” or variations of such words and phrases and similar expressions or statements that certain actions, events

or results "may", "could", "would", "might" or "will" be taken, occ ur or be achieved or the negative connotation of such

terms.

Such statements in this news release include, without limitation, statements with respect to planned exploration

programs, focuses, strategies, drilling targets and work, potential for further exploration of certain areas, potential drilling

results and related expectations, costs and expenditures, including with respect to the cost of development and

production, project economics, gold price assumptions, potential mineralization, projected ore grades, opportunities to

add near mine and further high -grade Mineral Reserves and Resources, expectations regarding the mine plan,

sustaining capital and value of operations and other statements and information that is based on forecasts and

projections of future operational, geological or financial results, estimates of amounts not yet determinable and

assumptions of management.

Exploration results that include geophysics, sampling, and drill results on wide spacings may not be indicative of the

occurrence of a mineral deposit. Such results do not provide assurance that further work will establish sufficient grade,

continuity, metallurgical characteristics and economic potential to be classed as a category of Mineral Resource. A

Mineral Resource that is classified as "inferred" or "indicated" has a great amount of uncertainty as to its existence and

economic and legal feasibility. It cannot be assumed that any or part of an "Indicated Mineral Resource" or "Inferred

Mineral Resource" will ever be upgraded to a higher category of Mineral Resource. Investors are cautioned not to

assume that all or any part of mineral deposits in these categories will ever be converted into Proven and Probable

Mineral Reserves.

Alamos cautions that forward -looking statements are necessarily based upon several factors and assumptions that,

while considered reasonable by management at the time of making such statements, are inherently subject to

significant business, economic, technical, legal, political and competitive uncertaintie s and contingencies. Known and

unknown factors could cause actual results to differ materially from those projected in the forward-looking statements,

and undue reliance should not be placed on such statements and information.

These factors and assumption s include, but are not limited to: the actual results of current exploration activities,

conclusions of economic and geological evaluations, changes in project parameters as plans continue to be refined,

operations may be exposed to illness, disease, epidemic or pandemic ; any ongoing or future impact of COVID -19 on

the broader market; state and federal orders or mandates (including with respect to mining operations generally or

auxiliary businesses or services required for the Company’s operations) in Cana da, Mexico and other jurisdictions in

which the Company does or may conduct business; the duration of regulatory responses to any illness, disease,

epidemic or pandemic; changes in national and local government legislation, controls or regulations; failure to comply

with environmental and health and safety laws and regulations; labour and contractor availability (and being able to

secure the same on favourable terms); ability to sell or deliver gold doré bars; disruptions in the maintenance or

provision of required infrastructure and information technology systems; fluctuations in the price of gold or certain other

commodities such as, diesel fuel, natural gas, and electricity; operating or technical difficulties in connection with mining

or development acti vities, including geotechnical challenges and changes to production estimates (which assume

accuracy of projected ore grade, mining rates, recovery timing and recovery rate estimates and may be impacted by

unscheduled maintenance); changes in foreign excha nge rates (particularly the Canadian dollar, U.S. dollar, and

Mexican peso); the impact of inflation; employee and community relations; litigation and administrative proceedings ;

disruptions affecting operations; availability of and increased costs associated with mining inputs and labour; delays in

the development or updating of mine plans; inherent risks and hazards associated with mining and mineral processing

including environmental hazards, industrial accidents, unusual or unexpected formations, pressures and cave-ins; the

risk that the Company’s mines may not perform as planned; uncertainty with the Company's ability to secure additional

capital to execute its business plans; the speculative nature of mineral exploration and development, risks in obtaining

and maintaining necessary licenses, permits and authorizations, contests over title to properties; expropriation or

nationalization of property; political or economic developments in Canada or Mexico and other jurisdictions in which

the Company may carry on business in the future; increased costs and risks related to the potential impact of climate

change; the costs and timing of construction and development of new deposits; risk of loss due to sabotage, protests

and other civil disturbances; the impact of global liquidity and credit availability and the values of assets and liabilities

based on projected future cash flows; and business opportunities that may be pursued by the Company.

For a more detailed discussion of such risks and other factors that may affect the Company's ability to achieve the

expectations set forth in the forward-looking statements contained in this news release, see the Company’s latest 40 -

F/Annual Information Form and Management’s Discussion and Analysis, each under the heading “Risk Factors”,

available on the SEDAR website at www.sedar.com or on EDGAR at www.sec.gov. The foregoing should be reviewed

in conjunction with the information and risk factors and assumptions found in this news release.