Ownership	100% IAG	Location	Quebec, Canada
Status	Resource development	Commodity	Gold
Deposit	Open Pit & Underground
Reserves	-	M&I Resources Inf. Resources	4.3 Moz 7.5 Moz

The Nelligan Mining Complex is a district-scale gold development platform located in the Chibougamau region of Québec, Canada. Following IAMGOLD’s completed acquisitions of Northern Superior and Orbec in December 2025, the Complex now consolidates a significant regional land position that includes Nelligan, Monster Lake, Philibert, Chevrier and several additional exploration targets.

The Complex hosts total combined Mineral Resources of 4.3 million ounces of Indicated resources at 0.99 g/t Au and 7.5 million ounces of Inferred resources at 1.08 g/t Au, positioning Nelligan among the largest pre-production gold projects in Canada. All primary deposits are located within a 17-kilometre radius, supporting IAMGOLD’s vision of a central processing facility fed by multiple ore sources within the region. A Preliminary Economic Assessment is expected in the first half of 2027. IAMGOLD’s total land position of 134,018 hectares positions the Company as the largest landholder in the region.

Regional land position highlighting primary deposits and exploration targets across the Chibougamau camp.

 

Reserves and Resources

	Tonnes (000s)	Grade (g/t)	Ounces (000s)
Nelligan
Indicated Mineral Resources Inferred Mineral Resources	122,000 151,000	0.95 0.96	3,700 4,647
Monster Lake
Indicated Mineral Resources Inferred Mineral Resources	243 1,046	13.04 14.83	102 499
Philibert
Indicated Mineral Resources Inferred Mineral Resources	7,884 48,465	1.10 1.10	279 1,709
Chevrier
Indicated Mineral Resources Inferred Mineral Resources	6,400 15,660	1.26 1.30	260 652

Figure - Nelligan 2024 Pit Shell (NE)

Location

The Nelligan Mining Complex is located in the Chibougamau region of Québec. Nelligan is located approximately 60 kilometres southwest of Chibougamau, and Monster Lake is located approximately 15 kilometres north of Nelligan.

The Complex benefits from a compact regional footprint, with Nelligan, Monster Lake, Philibert, Chevrier and other exploration targets located within the broader Chibougamau camp.

2026 Exploration Program

IAMGOLD’s exploration program at the Nelligan Mining Complex is focused on resource growth, improving resource confidence and testing extensions of known mineralized zones.

The program includes:

• Nelligan: 18,000 metres planned, with 9,400 metres completed
• Monster Lake: 15,000 metres planned, with 7,300 metres completed
• Philibert: 20,000 metres planned, increasing to 30,000 metres, with 14,000 metres completed

Other exploration targets include Muus, Lac Surprise, Anik and Lac Bossé. The Muus property is located at the intersection of two major mineralized structural breaks hosting Nelligan and Philibert, highlighting the broader exploration potential across the Complex. IAMGOLD holds a 75% interest in the Anik project.

Geology & Mineralization

The Nelligan Project is located in the northeastern corner of the Abitibi Sub-province of the Archean Superior Province, approximately 15 km west of the metamorphic border of the Mesoproterozoic aged Grenville Province, named as Grenville Front. The Abitibi Greenstone Belt is located in the southern part of the Superior craton, Canada and is composed of Greenschist- to sub-greenschist-grade rocks. 

The Project is hosted within the southern portion of the Chibougamau mining camp, known as Caopatina-Desmaraisville segment, which is bordered to the north by the Archean Opatica sub-province, to the east by the Proterozoïc Grenville front and to the south by a large cover of magmatic rocks known as Hébert pluton. The area is composed of volcanic and sedimentary rocks resulting from two complete volcano-sedimentary cycles.  

The Project is located along a major shear corridor on the northern part of the property, stretching for a strike length of four kilometres. The mineralization consists of two principal phases: The first phase is characterized by pervasive sericite-silica-potassic alteration, and is associated with fine-grained, disseminated automorphic pyrite (Pyrite I). The second phase of mineralization is attributed to orogenic hydrothermal fluids, marked by the presence of carbonates (calcite and dolomite) and medium-grained pyrite (Pyrite II), which are expressed in veinlets and stockworks, occasionally becoming semi-massive. 

The Nelligan deposit is comprised of five major mineralized zones, subdivided into 13 distinct subzones. The Renard Zone (Renard, Renard_2) is the principal zone of the deposit, extending three kilometres with significant silicification, sericite, and potassic alteration. This zone is offset by cross-cutting shear zones, creating sigmoidal shapes. The Footwall Zone (FW), the northernmost zone, extends over four kilometres and hosts quartz-carbonate veinlets with sub-automorphic pyrite, associated with visible gold in some areas. The Footwall East Zone (FW_E) is the eastern extension of this zone, displaced by a cross-cutting structure.

HISTORY

On December 19, 2025, and December 22, 2025, IAMGOLD acquired all of the issued and outstanding shares of Northern Superior and Orbec, respectively, by way of court-approved plan of arrangement for consideration of approximately $329.0 million and $14.2 million, respectively, in shares of the Company and cash. The Northern Superior acquisition consolidated the Philibert, Chevrier, Lac Surprise, and Croteau projects with Orbec’s early-stage Muus project, creating a combined project portfolio alongside IAMGOLD’s Nelligan, Monster Lake and Anik projects.

Nelligan

The Nelligan Project's ownership history dates back to an option agreement between Vanstar and IAMGOLD in 2014. In 2023, IAMGOLD acquired all of Vanstar’s outstanding shares, fully consolidating ownership of the Project. 

Exploration at Nelligan dates back to the 1950s, with early prospecting, mapping, and geophysical surveys driven by interest in the nearby Joe Mann deposit. Significant exploration began in the late 1970s, with companies such as Falconbridge, SOQUEM, and various juniors companies conducting geophysical surveys, drilling, and geochemical sampling. From 2012 to 2014, Vanstar identified key gold-bearing zones through magnetic surveys and drilling, leading to the 2014 option agreement with IAMGOLD.

Monster Lake

Resumption of exploration activities started in 2023 and involved evaluating various regional targets developed from targeting exercises to guide future drilling programs and to update the Mineral Resource Estimation with drill results obtained subsequent to the completion of the last estimation. In 2024, 5,900 metres of drilling were completed—3,500 metres in Q1 along the Monster Lake Shear Zone and 1,800 metres in Q4 to test resource extensions. On October 23, 2024, the Company reported an updated Mineral Resource Estimate.