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AGI.TO ·

Alamos Gold Extends High-Grade Gold Mineralization within Multiple Zones Across the Island Gold Deposit and Two Regional Exploration Targets

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 Extends High-Grade Gold Mineralization within Multiple Zones

Across the Island Gold Deposit and Two Regional Exploration Targets

Toronto, Ontario (November 9, 2023) – Alamos Gold Inc. (TSX:AGI; NYSE:AGI) (“Alamos” or

the “Company”) today reported new results from its near mine and regional exploration drilling

program at Island Gold. Un derground exploration drilling continues to extend high-grade gold

mineralization across the Island Gold Deposit within the main E1E and C -Zones, as well as

several hanging wall and footwall structures in proximity to existing underground infrastructure.

Additionally, the regional exploration program has been successful in intersecting high-grade gold

mineralization at two early-stage targets.

Island Gold Mine – main zone exploration highlights: high-grade mineralization extended

outside of Mineral Reserves and Resources in the E1E and C-Zones. These zones are the

main structures which host the majority of currently defined Mineral Reserves and

Resources at Island Gold. New highlights include1:

• Island East (E1E-Zone)

• 95.41 g/t Au (30.42 g/t cut) over 3.02 m (840-578-26);

• 118.59 g/t Au (61.74 g/t cut) over 2.31 m (1015-640-12);

• 62.09 g/t Au (61.83 g/t cut) over 2.19 m (840-632-24); and

• 37.33 g/t Au (33.16 g/t cut) over 2.56 m (840-608-52).

• Island West (C-Zone)

• 40.12 g/t Au (40.12 g/t cut) over 2.02 m (790-479-29);

• 17.23 g/t Au (17.23 g/t cut) over 3.02 m (790-479-22); and

• 23.79 g/t Au (23.79 g/t cut) over 2.05 m (790-479-20).

Island Gold Mine – hanging wall and footwall zone exploration highlights: high-grade gold

mineralization continues to be intersected within a number of new and recently defined

hanging wall and footwall zones across the main Island Gold Deposit. These zones

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

would be low cost to develop and produce given their proximity to existing infrastructure. New

highlights include1:

• Island East Footwall Zones

NTH4 Zone

• 168.03 g/t Au (27.88 g/t cut) over 3.14 m (840-632-21);

• 43.33 g/t Au (24.58 g/t cut) over 2.00 m (840-632-43);

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

2 | ALAMOS GOLD INC

• 25.94 g/t Au (13.92 g/t cut) over 3.14 m (840-632-32); and

• 19.55 g/t Au (11.36 g/t cut) over 2.03 m (840-632-25).

E1D1 Zone

• 47.62 g/t Au (20.19 g/t cut) over 2.78 m (945-624-15);

• 41.40 g/t Au (12.13 g/t cut) over 2.16 m (945-624-16);

• 22.12 g/t Au (6.17 g/t cut) over 3.77 m (945-624-28); and

• 17.32 g/t Au (11.84 g/t cut) over 3.81 m (945-624-19A).

E1D Zone

• 17.84 g/t Au (10.07 g/t cut) over 3.57 m (945-624-28); and

• 22.71 g/t Au (22.71 g/t cut) over 2.53 m (945-624-29).

• Island West Hanging Wall Zones: the NS1 zone has now been interpreted to have an

average North-South strike of approximately 70 m, with vertical continuity of over 400

m and remains open up and down dip. This zone was not factored into the 2023 mine plan

but is currently being developed and mined after being defined earlier this year. New

highlights include1:

• 121.37 g/t Au (15.47 g/t cut) over 2.65 m (770-475-01);

• 34.08 g/t Au (16.28 g/t cut) over 5.40 m (770-475-12);

• 23.46 g/t Au (10.16 g/t cut) over 2.14 m (770-475-14); and

• 21.89 g/t Au (8.45 g/t cut) over 2.20 m (770-475-13).

• Island West Footwall Zones (DN zone sub-parallel structure). New highlights include1:

• 47.44 g/t Au (12.02 g/t cut) over 2.43 m (790-479-35);

• 13.97 g/t Au (13.78 g/t cut) over 2.59 m (790-479-33); and

• 13.78 g/t Au (13.78 g/t cut) over 2.48 m (790-479-36).

1 All reported drill widths are true width of the mineralized zones, unless otherwise stated. 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; NS1 Zone @ 60 g/t Au; D1 and G1 Zones @ 45 g/t Au; G Zone @ 70 g/t

Au; E1D @ 80g/t Au; DN, E1D1, NTH1, NTH2, NTH3, NTH4 @ 35 g/t Au.

Regional exploration highlights: high-grade mineralization inte rsected at two regional

targets in proximity to the Island Gold operation. New highlights include2:

• Pine Zone: 4 kilometres (“km”) northeast of the Island Gold Mine

• 29.77 g/t Au over 9.31 m (23IGX057), including:

o 59.15 g/t Au over 4.39 m, including:

o 378.00 g/t Au over 0.37 m

• 3441.64 g/t Au over 0.67 m (23IGX043), including:

o 6220.00 g/t Au over 0.37 m

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• 79.44 g/t Au over 4.06 m (23IGX053), including:

o 932.00 g/t Au over 0.33 m

• 7.22 g/t Au over 7.45 m (23IGX055), including:

o 11.87 g/t Au over 3.43 m

• 3.12 g/t Au over 9.64 m (23IGX059), including:

o 20.10 g/t Au over 0.36 m

Adjacent Vein Arrays

• 6.44 g/t Au over 7.26 m (23IGX050), including:

o 63.1 g/t Au over 0.52 m

• 17.67 g/t Au over 1.44 m (23IGX053), including:

o 23.60 g/t Au over 1.05 m

• 88-60 Zone: 7 km from the Island Gold Mine, in proximity to the historic Cline and

Edwards mines:

• 6.00 g/t Au over 11.18 m (23IGX066), including:

o 19.79 g/t Au over 1.12 m

o 20.90 g/t Au over 0.78 m

o 24.60 g/t Au over 0.58 m

• 14.62 g/t Au over 1.5 m (23IGX066), including:

o 21.80 g/t over 0.94 m;

• 6.19 g/t Au over 3.31 m (23IGX065), including:

o 55.50 g/t over 0.34 m.

2 Regional exploration drillhole composite intervals reported as uncut, composites lengths are reported as core length,

true widths are estimated at 40 to 85% of core length. Composites are calculated with a 0.5 g/t cut-off, maximum internal

waste of 4 m, and no minimum thickness. Higher-grade intervals within the primary drillhole composite are reported as

“Including” for any individual or consecutive samples with assay grades greater than 10 g/t Au.

“We continue to see excellent results from our exploration program at Island Gold across multiple

areas of focus. The transition from surface directional drilling to underground drilling this year has

been a success as we leverage our existing underground infrastructure. We are extending high-

grade mineralization across the lateral extent of the main Island Gold deposit while also defining

and growing an increasing number of new zones within the hanging wall and footwall. Our success

on both fronts demonstr ates the significant potential for the addition of high -grade Mineral

Reserves and Resources near our existing underground development. This is providing

increasing operational flexibility and additional ounces that will be low -cost to develop, some of

which are already being mined, highlighting the near-term opportunities,” said John A. McCluskey,

President and Chief Executive Officer.

“We are also very encouraged by the early results out of our regional exploration program with

multiple high-grade intersections across the Pine and 88 -60 targets. These early-stage targets

are a good illustration of the excellent potential for additional high -grade deposits to be defined

across our large 55,300 hectare land package, which we more than tripled in size earlier this

year,” Mr. McCluskey added.

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

4 | ALAMOS GOLD INC

New highlight intercepts can be found in Tables 1 and 2, and in Figures 1 to 3 at the end of this

news release.

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, 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

Phase 3+ expansion ramping up, the focus has shifted to a more cost -effective expanded

underground exploration drilling progra m 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.

A total of 45,000 m of underground exploration drilling has been planned for 2023. The focus is

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 s everal 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 32,459 m of underground exploration drilling, and 24,649 m of delineation drilling has

been completed as of October 31, 2023. A regional exploration program including a total of 8,439

m of drilling was also completed in 2023. The focus of this program was on advancing exploration

targets outside the Island Gold Deposit on the newly expanded 55,300 -hectare Island Gold

property, including the Pine-Breccia and 88-60 targets described below.

Island West

Underground Exploration Drilling

Underground drilling has further extended high-grade gold mineralization along strike, 150 m to

the west, and up plunge of existing Mineral Reserves and Resources in the middle portion of

Island West. Drilling is being conducted from the 580-level and the 790-level exploration drifts,

between vertical depths of 700 m and 1,100 m.

New highlights include (Figure 1, Table 1):

C-Zone

• 40.12 g/t Au (40.12 g/t cut) over 2.02 m (790-479-29);

• 17.23 g/t Au (17.23 g/t cut) over 3.02 m (790-479-22);

• 23.79 g/t Au (23.79 g/t cut) over 2.05 m (790-479-20); and

• 12.75 g/t Au (12.75 g/t cut) over 2.38 m (790-479-21).

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

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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 and

perpendicular 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, highlighting

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

existing production horizons and infrastructure. These potential high-grade Mineral Reserves and

Resource additions could be incorporated into the mine plan within the next several years and

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

NS1 Hanging Wall Zone

The NS1 zone is a north-striking structure with a high-angle orientation relative to the C-Zone that

was identified earlier in 2023. Ongoing drill testing, and five exploration sills have been completed

from the 750, 770, 790, 810, and 850-levels which have demonstrated excellent continuity, over

an average strike of 40 m to the south on these levels, and over 100 m vertically. Additional drilling

from the 580, 770, and 900 levels has now expanded the NS1 zone over a vertical extent of 400

m, from the 890 level to the 400 level, and defined an average strike of 70 m.

The first stope was mined from the NS1 Zone late in the third quarter of 2023 with grades

performing in line with annual guidance. The NS1 zone is beyond currently defined Mineral

Reserves and Resources and outside of the 2023 mine plan demonstrating the significant near-

mine opportunities to add additional high -grade production in the near term. In addition, other

north-striking high -angle structures have been identified across the deposit, which will be

evaluated further as underground exploration drilling advances.

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

NS1 Zone

• 121.37 g/t Au (15.47 g/t cut) over 2.65 m (770-475-01);

• 34.08 g/t Au (16.28 g/t cut) over 5.40 m (770-475-12);

• 23.46 g/t Au (10.16 g/t cut) over 2.14 m (770-475-14); and

• 21.89 g/t Au (8.45 g/t cut) over 2.20 m (770-475-13).

B-Zone

• 16.13 g/t Au (13.68 g/t cut) over 2.33 m (770-475-26).

G-Zone

• 15.34 g/t Au (13.60 g/t cut) over 1.99 m (580-473-28).

Island West Footwall Zone

Underground exploration drilling is also targeting and expand ing on previous drilling that

intersected high-grade gold mineralization within a sub-parallel structure in the footwall from the

790-level. Ongoing drilling has been successful in extending high-grade gold mineralization and

establishing further continuity within the DN structure (Table 1). This zone is located 100 m north

of the main C-Zone.

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

6 | ALAMOS GOLD INC

New highlights from the Island West Footwall DN zone include:

DN Zone

• 47.44 g/t Au (12.02 g/t cut) over 2.43 m (790-479-35);

• 13.97 g/t Au (13.78 g/t cut) over 2.59 m (790-479-33); and

• 13.78 g/t Au (13.78 g/t cut) over 2.48 m (790-479-36).

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):

• 95.41 g/t Au (30.42 g/t cut) over 3.02 m (840-578-26);

• 118.59 g/t Au (61.74 g/t cut) over 2.31 m (1015-640-12);

• 62.09 g/t Au (61.83 g/t cut) over 2.19 m (840-632-24);

• 37.33 g/t Au (33.16 g/t cut) over 2.56 m (840-608-52);

• 5.30 g/t Au (5.30 g/t cut) over 7.08 m (1015-624-08);

• 11.80 g/t Au (11.80 g/t cut) over 2.85 m (840-632-31); and

• 14.22 g/t Au (14.22 g/t cut) over 2.30 m (840-608-43B).

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 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, NTH3, NTH4, E1D, and E1D1 zones.

The NTH zones are located 60 to 110 m north of the main E1E -Zone, and the E1D1 and E1D

zones, 10 m and 30 m from the E1E-Zone, respectively.

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

NTH4 Zone (Figure 2):

• 168.03 g/t Au (27.88 g/t cut) over 3.14 m (840-632-21);

• 43.33 g/t Au (24.58 g/t cut) over 2.00 m (840-632-43);

• 25.94 g/t Au (13.92 g/t cut) over 3.14 m (840-632-32);

• 28.80 g/t Au (7.92 g/t cut) over 2.48 m (840-632-33);

• 21.38 g/t Au (8.52 g/t cut) over 2.05 m (840-632-23);

• 16.34 g/t Au (11.35 g/t cut) over 2.44 m (840-632-24);

• 19.55 g/t Au (11.36 g/t cut) over 2.03 m (840-632-25); and

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• 18.42 g/t Au (10.74 g/t cut) over 2.14 m (840-632-38).

NTH Zone

• 10.23 g/t Au (10.23 g/t cut) over 3.92 m (620-SIL-04).

E1D1 Zone

• 47.62 g/t Au (20.19 g/t cut) over 2.78 m (945-624-15);

• 41.40 g/t Au (12.13 g/t cut) over 2.16 m (945-624-16);

• 22.12 g/t Au (6.17 g/t cut) over 3.77 m (945-624-28);

• 17.32 g/t Au (11.84 g/t cut) over 3.81 m (945-624-19A); and

• 9.26 g/t Au (7.49 g/t cut) over 4.80 m (945-624-21).

E1D Zone

• 17.84 g/t Au (10.07 g/t cut) over 3.57 m (945-624-28); and

• 22.71 g/t Au (22.71 g/t cut) over 2.53 m (945-624-29).

As with the hanging and footwall zones in Island West, these footwall zones in Island East

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

production horizons and infrastructure which would be low-cost to develop and mine.

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 and defined

with step-out drilling from underground drill platforms.

This drilling allows for the confirmation of the geometry and potential continuity of mineralization

with the objective of defining new Mineral Resources. As demonstrated with the E1D, E1ED1,

NTH, NTH2, NTH3, NTH4 and perpendicular NS1 Zone, as well as the B, D, DN, G, and G1

Zones that were defined in 2022, a growing number of these zones are being defined as

underground development is established in these areas.

These zones and other targets within the hanging wall and footwall represent significant

opportunities to define additional Mineral Reserves and Resources outside of the main C/E1E -

Zone in proximity to existing underground development. These additions 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 as core length, true width is unknown at this time )

(Table 1):

Footwall Intersections:

• 148.67 g/t Au over 2.00 m (790-479-35);

• 68.95 g/t Au over 2.93 m (945-624-19A);

• 33.86 g/t Au over 2.91 m (840-554-66);

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• 37.57 g/t Au over 2.00 m (790-479-32);

• 26.31 g/t Au over 2.48 m (945-624-19A); and

• 30.25 g/t Au over 1.96 m (840-632-28).

Hanging Wall Intersections:

• 65.77 g/t Au over 2.00 m (580-473-39);

• 43.52 g/t Au over 2.84 m (770-475-28);

• 52.65 g/t Au over 2.00 m (900-506-06);

• 19.73 g/t Au over 3.73 m (945-624-20);

• 25.35 g/t Au over 2.66 m (770-475-22); and

• 17.21 g/t Au over 2.98 m (770-475-23).

Regional Exploration

The 2023 Regional Exploration program was successful in identifying high -grade gold

mineralization at multiple early-stage targets, highlighting the significant regional potential across

the 55,300 hectare Island Gold Property . A total of 8,439 m of regional exploration drilling has

been completed to date in 2023. The priority drilling targets in 2023 included the Pine-Breccia,

and 88-60 Zones, which are highlighted below.

Pine-Breccia Target (Figure 3)

Pine Zone

The Pine Zone is located approximately 4 km from the Island Gold Mine and comprises a sheared

sulphide unit truncated by the regional NNW -trending Maskinonge Lake F ault that hosts the

Breccia Zone ( Figure 3). The sulphide unit was identified through a l imited amount of historic

drilling prior to Alamos’ ownership . Follow up channel sampling completed by Alamos in 2022

confirmed and further defined the extent of high-grade mineralization. In 2023, 1,892 m of drilling

was completed in 11 holes following up on the channel sample results. The drilling was successful

in defining high-grade mineralization over an approximate strike extent of 50 m and depth of 150

m. This has been currently interpreted as a narrow , steeply plunging ore shoot, which remains

open down-plunge. Additional high-grade mineralization was intersected in vein arrays within 50

m of the Pine Zone, further supporting the presence of a significant high-grade gold system.

New highlights include (Table 2):

Pine Zone

• 29.77 g/t Au over 9.31 m (23IGX057), including:

o 59.15 g/t Au over 4.39 m, including:

o 378.00 g/t Au over 0.37 m

• 3441.64 g/t Au over 0.67 m (23IGX043), including:

o 6220.00 g/t Au over 0.37 m

• 79.44 g/t Au over 4.06 m (23IGX053), including:

o 932.00 g/t Au over 0.33 m