Alamos Gold Inc. (TSX:AGI) (NYSE:AGI) 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 extended 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 over 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).

• 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 their 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.

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 in 2022 to 45,000 m in 2023. The program is focused 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 exploration 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.

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 sills 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 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 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).

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 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 drilling 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.

Quality Assurance and Quality Control

Alamos Gold maintains an internal Quality Assurance / Quality Control 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 samples 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 being 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 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 Mulatos 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”.

Table 1: Island Gold – Previously Unreleased Select Composite Intervals from Underground Exploration Drilling

Composite intervals greater than 3 g/t Au weighted average, capping values:

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.

Table 2: Underground exploration drill holes; azimuth, dip, drilled length, and collar location at surface (UTM NAD83).

Note: UTM mine surface elevation 393 m

Figure 1: Island Gold Mine – C/E1E/E1EN/E1D Longitudinal, New C and E1E-Zone Underground Exploration Drilling Results

Figure 2: Island Gold West – Highlights from NS1 Hanging Wall Zone

Figure 3: Island Gold East – Highlights from NTH3 Footwall Wall Zone