Onyx Gold Intersects 52.2 M of 2.2 g/t Gold and 50.4 M of 1.9 g/t Gold at Argus North Zone, Munro-Croesus Project Mineralized Zone Extended to Surface Now Reaches Over 200 M Vertically Drill Program Increased to 25,000 M
July 23, 2025 NR# 030-2025
NEWS RELEASE
Onyx Gold Intersects 52.2 M of 2.2 g/t Gold and 50.4 M of 1.9 g/t Gold
at Argus North Zone, Munro-Croesus Project
Mineralized Zone Extended to Surface Now Reaches Over 200 M Vertically
Drill Program Increased to 25,000 M
Vancouver, BC – July 2 3rd, 2025 – Onyx Gold Corp. (“Onyx” or the " Company") ( TSX-V:
ONYX, OTCQX: ONXGF) is pleased to announce drill results for five (5) additional drill holes from
the Company’s drill program (the “Program’) at the Argus North Zone (“Argus North”), a newly
identified gold zone located on its 100% owned Munro-Croesus Project (“Munro-Croesus” or the
“Project”), 75 km east of Timmins, Ontario.
The results reported today are from five step-out drill holes completed on a cross-section located
50 metres (“m”) east of the Argus North discovery-hole section. This follows the June 2025 release
of four drill holes from the discovery section, which included a highlight intercept of 91.0 metres
grading 1.8 grams per tonne “g/t” gold (“Au”), with a higher -grade interval of 32.0 metres of 4.0
g/t Au in hole MC25-168 (see Company news release dated June 26, 2025).
Highlights
• 52.2 m grading 2.2 g/t Au including 5.2 m of 5.1 g/t Au, and a second deeper intersection
of 61.3 m of 1.5 g/t Au including 6.6 m grading 4.2 g/t Au, in drill hole MC25-178 for a
total cumulative width of 113.5 m of mineralization.
• 66.8 m grading 1.4 g/t Au including 4.0 m of 6.6 g/t Au, in drill hole MC25-179, a 50 m
up-dip step-out from drill hole MC25-178.
• 50.4 m grading 1.9 g/t Au starting at 6.1 m downhole (approximately 4 m vertically
from surface), including 4.0 m of 5.9 g/t Au, in drill hole MC25-180, a 50 m up-dip step-
out from drill hole MC25-179
• Results to date demonstrate excellent continuity of wide intervals of strong gold
mineralization now defined over 200 m vertically and extending right to surface
• The Company has completed 26 drill holes (assays announced for nine holes to date),
totaling approximately 9,000 m of the 10,000 m phase 1 program.
• Current drill program expanded from 10,000 m to 25,000 m.
“These latest results from Argus North continue to highlight strong gold grades over broad widths
and confirm that the zone remains open for expansion,” said Brock Colterjohn, President & CEO.
“We are particularly encouraged by the mineralization intersected essentially at surface as this
enables mechanical stripping to expose and sample the zone in outcrop : another useful
exploration tool. We are mobilizing an excavator to site now and are look forward to the additional
insights we can gather from surface work.”
“With results from just nine drill holes reported to date at Argus North, we’re already defining a
zone with notable grade and continuity that remains open along strike and down-plunge. Based
on these results, we’ve expanded the drill program to further test this emerging zone and to
explore additional high -priority targets across the broader Munro -Croesus project through the
second half of the year.”
Discussion of 2025 Argus North Results
The Argus North Zone is located on the western half of the Munro-Croesus project, 150 m north
of the regional Pipestone Fault, a major structural corridor known to host significant gold deposits.
Hole MC24-163, the discovery drill hole at Argus North reported earlier this year, returned 69.6 m
grading 3.4 g/t Au, including 34.5 m grading 5.4 g/t Au, including 9.5 m grading 13.9 g/t Au
(see Company news release dated April 10, 2025). Argus North is situated 100 m north of the
east-west trending main Argus Zone, which is a separate 750 m x 200 m near-surface bulk
tonnage target (e.g. 1.0 g/t Au over 63.3 m and 0.5 g/t Au over 136 m).
Mineralization at Argus North is hosted within a strongly brecciated structural zone with 3-10%
fine-grained disseminated pyrit e and distinct pyritic stringers that extend into the host mafic
variolitic basalts . Halos of s trong albitization, strong silicification, and locally moderate
sericitization are associated with the mineralized zones, often intruded by 1 to 7 m thick quartz ±
feldspar porphyritic intrusions . Drilling to date indicates an east -southeast strike and a steep
southerly dip to the Argus North structural zone, which may represent a secondary splay off the
regional scale Pipestone Fault. Gold mineralization at Argus North has been delineated between
surface and 200 m vertical depth, 50 m in an east-west direction, and remains open along strike
and down-plunge.
The five drill holes reported in this news release are all located on the same north -south cross-
section, 50 m east of previously reported drill holes MC24-163/168/171 (see Figure 1 and Figure
2) with approximate 50 m step-outs up-dip and down-dip. The drilling to date has continued to
return promising results with holes MC25-178, MC25-179 and MC23-180 all intersecting 50-to-
67-meter widths of consistent gold mineralization as reported below and in Table 1:
• 52.2 m grading 2.2 g/t Au, in hole MC25-178 (50 m east of drill hole MC25-168), including
o 32.2 m grading 3.0 g/t Au, including
▪ 5.2 m grading 5.1 g/t Au, AND
• 61.3 m grading 1.5 g/t Au, in hole MC250178, including
o 31.6 m grading 2.0 g/t Au, including
▪ 6.6 m grading 4.2 g/t Au
• 66.8 m grading 1.4 g/t Au, in hole MC25-179 (50 m up-dip from MC25-178), including
o 22.8 m grading 3.3 g/t Au, including
▪ 4.0 m grading 6.6 g/t Au
• 50.4 m grading 1.9 g/t Au starting at 6.1 m downhole, in hole MC25-180 (50 m up-dip
from MC25-179), including
o 24.5 m grading 3.4 g/t Au, including
▪ 4.0 m grading 5.9 g/t Au
• 36.3 m grading 0.4 g/t Au, in hole MC25-173 (60 m down-dip from MC25-178), including
o 1.9 m grading 3.7 g/t Au
• 1.1 m grading 12.0 g/t Au, in hole MC25-175 (50 m down-dip from MC25-173), with other
individual zones returning 1.1 to 2.5 m widths grading 1.1 to 3.5 g/t Au.
Next Steps
The Company has completed 26 drill holes totalling ~9,000 m to date as part of its fully funded
Phase 1 drill program at the Argus Zone. Ongoing plans include step-out drilling along strike on
50 m to 100 m spaced cross -sections designed to extend the limits of the known gold
mineralization.
The Company’s Board of Directors has approved a 150% increase in the size of the Program
from 10,000 to 25,000 m based on the strong results to date at Argus North. Additional drilling will
continue to systematically step out east and west along the key prospective variolitic basalt flows
immediately north of the Pipestone Fault and to target other high -priority targets over the large
109 km2 Project area.
In addition, the Company plans to excavate the near-surface mineralization intersected in the top
of hole MC25 -180 using mechanical stripping to complete detailed mapping and sampling of
outcrop. The Company also plans to complete ground-based direct-coupled induced polarization
(“DCIP”) geophysical surveying to infill the 200 m spaced gridlines completed in winter of 2021 -
2022 over Argus Main and Argus North.
The Munro-Croesus Project
The Munro-Croesus Project is located along Highway 101 in the heart of the Abitibi greenstone
belt, Canada's premier gold mining jurisdiction (Figure 3). This large, 100% owned land package
includes the past-producing Croesus Gold Mine, which yielded some of the highest -grade gold
ever mined in Ontario. Extensive land consolidation from 2020-2025 has unified the patchwork of
patented and unpatented mining claims surrounding the Croesus Gold Mine into one largely
coherent package and enhanced the project's exploration potential.
The Project covers 109 km 2 of highly prospective geology within the influence of major gold -
bearing structural breaks. Bulk-tonnage gold deposits located in the immediate region include the
Fenn-Gib gold project being developed by Mayfair Gold Corp. that contains an Indicated
Resource of 4.31 Moz at 0.74 g/t Au and an Inferred Resource of 141 koz at 0.49 g/t Au, and the
Tower Gold Project being developed by STLLR Gold Inc. that contains an open pit Indicated
Resource of 4.46 Moz at 0.92 g/t Au and an Inferred Resource of 8.29 Moz at 1.09 g/t Au1.
Figure 1 – Cross-Section Highlighting Drill Holes Reported in this Release – Looking East
Figure 2 – Plan Map Highlighting Argus North Zone Drill Holes Reported in this Release
Figure 3 – Location of the Munro-Croesus Gold Project, Ontario
Table 1 – Significant Assay Results from 2025 Drilling Completed at the Argus North Zone
Target From To Length Au
Drill Hole (m) (m) (m) (g/t)
Argus North
MC25-173 26.8 39.0 12.2 0.5
Including 26.8 27.4 0.6 4.3
And Including 37.0 38.0 1.0 1.8
And 219.4 240.5 21.1 0.5
Including 219.4 230.1 10.7 0.8
Including 225.0 230.1 5.1 1.1
And 259.9 296.2 36.3 0.4
Including 259.9 261.8 1.9 3.7
And Including 295.2 296.2 1.0 3.5
And 324.2 325.9 1.7 1.2
MC25-175 6.0 7.5 1.5 1.8
And 34.0 35.5 1.5 1.9
And 57.0 59.5 2.5 1.1
Including 58.5 59.5 1.0 1.6
And 169.3 170.4 1.1 1.1
And 247.0 248.1 1.1 12.0
And 289.0 291.0 2.0 1.6
Including 289.0 290.0 1.0 2.2
And 309.5 311.0 1.5 3.5
MC25-178 71.9 124.1 52.2 2.2
Including 91.0 123.2 32.2 3.0
Including 91.0 104.0 13.0 3.8
And including 118.0 123.2 5.2 5.1
And 147.0 208.3 61.3 1.5
Including 151.0 182.6 31.6 2.0
Including 162.0 168.6 6.6 4.2
And including 180.0 182.6 2.6 4.7
And Including 193.9 207.2 13.3 1.9
Including 193.9 199.0 5.1 2.4
MC25-179 13.8 73.0 59.2 0.3
Including 13.8 48.0 34.2 0.4
Including 15.8 18.8 3.0 1.4
And Including 58.0 61.0 3.0 1.4
And 101.0 167.8 66.8 1.4
Including 115.7 138.5 22.8 3.3
Including 115.7 125.7 10.0 4.4
Including 118.7 122.7 4.0 6.6
And Including 133.5 138.5 5.0 3.8
MC25-180 6.1 56.5 50.4 1.9
Including 32.0 56.5 24.5 3.4
Including 32.0 35.0 3.0 9.1
And Including 43.0 46.0 3.0 5.1
And Including 52.5 56.5 4.0 5.9
*Intersections are reported as drilled width; true width is estimated to be 70-90% of drilled width.