Overview

Located less than 15 km from Newmont’s Éléonore gold mine in the Eeyou Istchee James Bay territory of Québec, the Cheechoo property, 100% owned by Sirios, contains an untapped gold deposit with excellent expansion and development potential, for both large-volume open-pit extraction and high-grade underground mining.

Size

15,700 ha

Ownership

100%-Owned,
with a royalty of up to 4% of the net returns granted to Gold Royalty Corp

Open-pit potential

1.4 million ounces at an average grade of 0.94 g/t Au (Indicated Resources)
500,000 ounces at an average grade of 0.73 g/t Au (Inferred Resources)
Low strip ratio (2.3:1)

Underground potential

A management review of data completed in mid-2024 identified multiple promising targets for delineating high-grade zones that may lead to underground mining.
Prospects identified include the near-surface Eclipse zone.

The Cheechoo Gold Deposit

The Cheechoo Project contains multiple gold-enriched zones encased in a lower-grade halo. The deposit is hosted in a folded tonalite intrusion surrounded by metasedimentary rocks similar to those hosting the Éléonore mine.

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Sections of the Eclipse High-Grade Zone

The near-surface Eclipse zone exhibits remarkable high-grade continuity across numerous drill holes:

Potential additional high-grade zones

Numerous high-grade gold intercepts outside the Eclipse zone suggest the occurrence of additional high-grade zones:

Au (g/t)Length (m)From (m)To (m)Drill holeZone
30.18.0317.2325.2CH17-112Outside*
30.47.1130.5137.6CH16-052Outside*
9.516.8132.5149.3CH16-041Outside*
21.57.074.081.0CH16-035Outside*
8.816.321.137.4CH21-280Outside*
31.34.6162.3166.9CH21-295Outside*
65.12.199.5101.6CH17-095Eclipse Zone
9.714.0125.0139.0CH17-112Outside*
27.54.882.287.0CH19-245Outside*
41.33.117.520.6CHRN17-213Outside*
13.89.0270.5279.5CH20-265Outside*
15.87.4110.0117.4CH21-285Outside*
26.64.3115.5119.9CH15-020Outside*
55.72.064.066.0CH19-202Eclipse Zone
12.29.185.094.1CH18-191Outside*
21.25.2562.5567.7CH17-108Outside*
11.39.538.047.5CH15-028Outside*
22.74.6213.9218.5CH20-266Outside*
15.36.8336.0342.8CH19-240Outside*
12.98.0294.0302.0CH17-132Outside*
26.43.9143.6147.5CH18-184Outside*
28.43.662.566.1CH16-086Outside*
34.13.0425.0428.0CH17-098Outside*
50.52.077.579.5CH19-201Eclipse Zone
24.04.232.036.2CH16-079Outside*
10.09.957.667.5CH18-182Outside*
17.15.8228.1233.9CH17-125Outside*
7.013.819.132.9CH21-279Outside*
11.78.0105.0113.0CHRC21-002Outside*
37.32.5440.7443.2CH18-125EOutside*
18.84.9202.5207.4CH18-183Outside*
24.03.8152.0155.8CH17-134Outside*
28.33.259.162.3CH18-159Outside*
18.94.659.564.1CH15-020Outside*
17.54.9253.0257.9CH24-305Eclipse Zone
5.216.2174.9191.1CH15-024Outside*
11.87.0121.5128.5CH18-191Outside*
34.22.490.092.4CH18-163Eclipse Zone
37.12.291.894.0CH18-161Eclipse Zone
16.25.0280.5285.5CH20-258Outside*
15.85.0261.0266.0CH16-058EOutside*
9.68.2221.3229.5CH17-139Outside*
27.82.8156.6159.4CH17-112Outside*
17.04.525.830.3CH19-199Eclipse Zone
18.04.2104.8109.0CH21-283Outside*
18.84.0117.5121.5CH16-088Outside*
11.86.3130.0136.3CH16-088Outside*
13.15.596.1101.6CH18-176Outside*
12.85.5138.5144.0CH14-017Outside*
5.014.1322.6336.7CH18-181Outside*
3.419.7258.1277.8CH17-122Outside*
30.12.2125.8128.0CH17-124Outside*
25.62.436.839.2CH18-192Outside*
13.14.6107.3111.9CH16-065Outside*
30.22.0137.5139.5CH19-204Eclipse Zone
15.14.0325.0329.0CH17-111Outside*
18.73.2232.0235.2CH21-288Outside*
14.73.955.058.9CH15-026Outside*
24.82.3189.2191.5CH21-296Outside*
18.93.0123.0126.0CH18-196Outside*
22.92.47.39.7CH17-119Outside*
14.73.7137.0140.7CH17-128Outside*
12.84.282.786.9CH16-054Outside*
21.32.5323.0325.5CH17-109Outside*
25.82.044.746.7CH17-099Eclipse Zone
9.05.6213.5219.0CH13-010Outside*
13.73.637.340.9CH18-182Outside*
10.64.5214.0218.5CH17-128Outside*
6.37.5152.5160.0CH17-123Outside*
7.86.0134.5140.5CH17-098Outside*
16.12.5173.4175.9CH21-274Outside*
7.74.7278.1282.8CH17-108Outside*
5.46.758.365.0CH19-221Outside*
7.15.0111.0116.0CH15-024Outside*
13.32.5130.6133.1CH14-018Outside*
7.14.4305.6310.0CH17-111Outside*
9.83.0367.0370.0CH16-062Outside*
11.02.625.528.1CH17-112Outside*
Grade capped at 100 g/t Au. Lengths along drill hole.

*High-grade gold intercepts located outside the Eclipse zone

Next Phases of Development

“We are thrilled to launch this new vision for the Project. Cheechoo now presents dual potential: large-volume open-pit mining and/or high-grade underground development. This new outlook is a game changer for the Project, consequently leading our team to design an intensive drilling program targeting high-grade enriched zones.”
Dominique Doucet, CEO and President

Planned drilling program

Sirios' technical team is currently designing an intensive drilling program aimed at delineating high-grade zones within the property. The company intends to disclose comprehensive details about this strategic program in forthcoming press releases, offering stakeholders valuable insights into Sirios' exploration plans and objectives.

Mineral Resource Estimate (MRE) Update

MRE update scheduled post-drilling
To underpin forthcoming PEA

A Prime Location

The Cheechoo property is ideally located for mining development:

Year-round road access via Billy-Diamond Highway and Éléonore mine road
161 kV power line just 5 km from deposit
Éléonore mining infrastructure <15 km away, including underutilized mill
Québec ranked #5 globally for mining investment (Fraser Institute, 2023)
Positive engagement with Cree Nation of Wemindji

Discover Cheechoo and More on Our Project Portfolio Map.

Geological Setting

The Cheechoo property is located at the suture zone between two geological subprovinces: the Opinaca and La Grande. The Opinaca Subprovince contributes paragneissic wacke and migmatites, while the La Grande Subprovince provides banded iron formations and mafic dykes. The centerpiece of the property is the Cheechoo intrusion, dated at 2612 Ma, which is roughly contemporaneous with other granitic suites in the region.

Cheechoo Intrusion Characteristics

The Cheechoo intrusion displays variable textures, ranging from massive to gneissic, indicating a complex magmatic and metamorphic history. It has a granodioritic to trondhjemitic composition, with metaluminous to peraluminous tendencies and a reduced nature. The intrusion is notably high in sodium content, likely due to an early gold-related sodic metasomatic event.

Gold Mineralization

Gold mineralization is primarily hosted within the Cheechoo intrusion, with some occurrences in surrounding metasedimentary rocks, pegmatite dykes, and mafic schists. The mineralization is characterized by networks of quartz veins with associated calc-silicate and potassic alteration. High-grade gold veins typically contain less than 5% disseminated sulfides and often display visible gold.

Metallogenic Model

The structural characteristics of the gold system suggest a syn-tectonic emplacement of the Cheechoo intrusion and related gold-bearing vein networks. The mineralogy, alteration assemblages, and association with a reduced intrusion bear similarities to reduced intrusion-related gold systems. This represents a new style of gold mineralization in the Eeyou Istchee James Bay region.

NI 43-101 Technical Report

Latest Updates on the Cheechoo Project