Radisson Step-Out Drilling at O'Brien Gold Project Intersects High-Grade Mineralization in Multiple Locations
Radisson Step-Out Drilling at O'Brien Gold
Project Intersects High-Grade Mineralization
in Multiple Locations
Rouyn-Noranda, Quebec--(Newsfile Corp. - October 28, 2025) -
Radisson Mining Resources Inc.
(TSXV: RDS) (OTCQX: RMRDF)
("
Radisson
" or the "
Company
") is pleased to announce assay
results from fifteen new drill holes completed at its 100%-owned O'Brien Gold Project ("
O'Brien
" or the
"
Project
") located in the Abitibi region of Québec. The fifteen holes represent step-outs below the
existing geological model and the historic O'Brien Gold Mine and are part of an ongoing 140,000-metre
drill program designed to test the overall scope of gold mineralization at the Project (see
Radisson news
release dated October 16, 2025
). All holes intersected gold mineralization in characteristic quartz-
sulphide-gold veins within alteration zones, and thirteen of the holes returned intercepts with grades and
thicknesses consistent with the Project's existing mineral resources.
Today's results include significant intercepts in three separate step-out locations (Figures 1 & 2), each of
which has significance for the potential future growth of the Project's mineral resources. These are:
Between Trends #1 and #2 at 1,000 Metres Vertical Depth
OB-25-371W5
intersected 10.50 grams per tonne ("g/t") gold ("Au") over 6.5 metres, including
14.90 g/t Au over 1.5 metres and including 16.95 g/t Au over 1.0 metre
OB-25-371W4
intersected 11.25 g/t Au over 2.5 metres, including 17.80 g/t Au over 1.5 metres
OB-25-371W6
intersected 4.51 g/t Au over 9.0 metres, including 10.70 g/t Au over 1.5 metres
Beneath the Historic "O'Brien Mine West" at 1,000 Metres Vertical Depth
OB-25-376W1
intersected 9.16 g/t Au over 2.5 metres, including 14.70 g/t Au over 1.1 metres
OB-25-376
intersected 8.05 g/t Au over 2.50 metres, including 15.75 g/t Au over 1.0 metre
Beneath the Historic "O'Brien Mine" at 1,100 Metres Vertical Depth
OB-24-337W11
intersected 7.00 g/t Au over 3.0 metres, including 12.60 g/t Au over 1.5 metres,
and
13.00 g/t Au over 1.50 metres
Matt Manson, President & CEO, commented:
"Today's drill results illustrate the extension of classic,
high-grade O'Brien gold mineralization across a broad front. We are reporting the first high-grade
intercepts beneath the western portion of the historic mine, with drill hole OB-25-376W1 extending
mineralization 160 metres below the former mine in this area. Drill hole OB-24-337W11 demonstrates
continuity of high-grade mineralization below the main stope of the historic mine. Of particular note,
drill holes OB-25-371W4 to W6 returned high-grade mineralization on the western edge of the deep
extension of Trend #2, close to the observed extension of Trend #1 (Figures 1&2). This suggests that
the apparent gap between these two trends is a function of drill coverage rather than geology, as we
have suspected. Closing this gap with new drilling is a priority. With a fully-funded 140,000-metre drill
program ongoing and an increase in rigs from the current four to an eventual eight, we are casting a
wide net at O'Brien and seeing consistent success."
Figure 1
: Longitudinal Vertical Section and Plan View of Gold Vein Mineralization and Mineral
Resources at the O'Brien Gold Project, with Today's Drill Holes Illustrated
To view an enhanced version of this graphic, please visit:
https://images.newsfilecorp.com/files/10977/272164_3fafb92ae4c30b1d_002full.jpg
Table 1
: Assay Results from Select Drill Holes
DDH
Zone
From (m)
To (m)
Core Length (m)
Au g/t - Uncut
Host Lithology
OB-24-337W8
O'Brien Mine
1,529.0
1,530.5
1.50
5.33
S1p
1,605.8
1,607.8
2.00
3.25
ZFLLC
OB-24-337W9
O'Brien Mine
Including
1,381.0
1,382.0
1.00
3.12
PON-S3
OB-24-337W10
O'Brien Mine
870.0
871.5
1.50
5.24
PON-S3
877.5
879.0
1.50
4.86
PON-S3
Including
1,270.0
1,271.0
1.00
4.93
POR-S
1,221.0
1,222.5
1.50
5.46
V3-S
OB-24-337W11
O'Brien Mine
1,271.5
1,274.5
3.00
7.00
V3-CEN
Including
1,273.0
1,274.5
1.50
12.60
V3-CEN
1,305.1
1,306.6
1.50
13.00
POR-N
1,312.5
1,315.5
3.00
3.00
V3-N
Including
1,314.0
1,315.5
1.50
4.66
V3-N
OB-25-371W2
Trend #2
1,188.2
1,189.5
1.30
5.63
V3-S
1,251.0
1,252.5
1.50
7.18
V3-S
OB-25-371W4
Trend #2
Including
1,086.0
1,087.5
1.50
4.04
V3-S
1,139.5
1,142.0
2.50
11.25
V3-S
Including
1,139.5
1,141.0
1.50
17.80
V3-S
OB-25-371W5
Trend #2
1,158.7
1,165.2
6.50
10.50
V3-S
Including
1,160.0
1,161.5
1.50
14.90
V3-S
Including
1,163.0
1,164.0
1.00
16.95
V3-S
1,228.5
1,230.0
1.50
4.75
POR-S
OB-25-371W6
Trend #2
1,071.0
1,080.0
9.00
4.51
V3-S
Including
1,072.5
1,074.0
1.50
10.70
V3-S
1,103.0
1,104.5
1.50
3.67
POR-S/V3-CEN
OB-25-376
O'Brien Mine West
544.5
547.0
2.50
8.05
PON-S3
Including
544.5
545.5
1.00
15.75
PON-S3
1,068.0
1,069.5
1.50
4.22
POR-S
1,091.0
1,092.5
1.50
6.97
V3-CEN
1,144.0
1,147.0
3.00
3.71
POR-N
OB-25-376W1
O'Brien Mine West
1,065.6
1,068.1
2.50
9.16
S1p
Including
1,067.0
1,068.1
1.10
14.70
S1P
OB-25-376W2
O'Brien M.W.
1,076.3
1,077.5
1.20
7.02
S1p
OB-25-376W3
O'Brien M.W.
989.5
990.5
1.00
5.19
S1p
OB-25-376W5
O'Brien Mine West
1,059.5
1,062.0
2.50
3.55
V3-CEN/S1p
1,094.5
1,096.0
1.50
3.98
S1p
Notes on Calculation of Drill Intercepts:
The O'Brien Gold Project Mineral Resource Estimate effective May 6, 2025 ("MRE") utilizes a 2.20 g/t Au bottom cut-off, a US$2,000 gold price, a
minimum mining width of 1.2 metres, and a 40 g/t Au upper cap on composites. Intercepts presented in Table 1 are calculated with a 3.00 g/t Au
bottom cut-off. True widths, based on depth of intercept and drill hole inclination, are estimated to be 30-80% of core length. Table 2 presents
additional drill intercepts calculated with a 1.00 g/t bottom cut-off over a minimum 1.0 metre core length so as to illustrate the frequency and
continuity of mineralized intervals within which high-grade gold veins at O'Brien are developed. Lithology Codes: PON-S3: Pontiac Sediments; V3-
S, V3-N, V3-CEN: Basalt-South, North, Central; S1P, S3P: Conglomerate; POR-S, POR-N: Porphyry South, North; TX: Crystal Tuff; ZFLLC: Larder
Lake-Cadillac Fault Zone.
Figure 2
: Longitudinal Vertical Section of Gold Vein Mineralization and Mineral Resources at the
O'Brien Gold Project, with Deep Step-Out Drill Holes Completed and/or Published by the Company
since December 2024.
To view an enhanced version of this graphic, please visit:
https://images.newsfilecorp.com/files/10977/272164_3fafb92ae4c30b1d_004full.jpg
Gold Mineralization at O'Brien
Gold mineralizing quartz-sulphide veins at O'Brien occur within a thin band of interlayered mafic volcanic
rocks, conglomerates, and porphyritic andesitic sills of the Piché Group occurring in contact with the
east-west oriented Larder Lake-Cadillac Break ("LLCB"). Gold, along with pyrite and arsenopyrite, is
typically associated with shearing and a pervasive biotite alteration, and developed within multiple Piché
Group lithologies and, occasionally, the hanging-wall Pontiac and footwall Cadillac meta-sedimentary
rocks.
As mapped at the historic O'Brien mine, and now replicated in the modern drilling, individual veins are
generally narrow, ranging from several centimetres up to several metres in thickness. Multiple veins
occur sub-parallel to each other, as well as sub-parallel to the Piché lithologies and the LLCB. Individual
veins have well-established lateral continuity, with near-vertical, high-grade shoots developed over
significant lengths. Based on the historic data available, it is clear that the former mine was "high-
graded", with mining focussed on a main central stope and parallel veins identified but left undeveloped.
The historic O'Brien mine produced over half a million ounces of gold from such veins and shoots at an
average grade exceeding 15 g/t Au and over a vertical extent of at least 1,000 metres. Modern
exploration has focussed on delineating well developed vein mineralization to the east of the historic
mine, with additional high-grade shoots becoming evident in the exploration data over what has been
described as a series of repeating trends ("Trend #s 0 to 5").
Step-Out Drilling at O'Brien
Since the end of 2024, Radisson has been pursuing a program of broad step-outs beneath the historic
O'Brien Gold mine and the existing mineral resources designed to test the extent of mineralization at the
Project. This drilling is accomplished with pilot holes followed by wedges and directional drilling to
maximize drill efficiency. On October 16, 2025 Radisson announced the expansion of the step-out drill
program to 140,000 metres employing an eventual eight drill rigs.
The origin of the step-out drill program was the deep pilot hole OB-24-337, which was the first
exploration drill hole located below the former mine workings since mining ended in 1957. This hole
intersected 31.24 g/t Au over 8.0 metres, including 242.0 g/t Au over 1.0 metre at approximately 1,500
metres vertical depth (see
Radisson news release dated December 16, 2024
). With today's results,
assay results from a total of 11 wedges from OB-24-337 have now been reported and up to six gold-
bearing veins have been delineated over an area of approximately 250 metres (east-west) by 500
metres (vertical). Included in today's results is the eleventh wedge, OB24-337-W11, which intersected
7.00 g/t Au over 3.0 metres, including 12.60 g/t Au over 1.5 metres, and 13.00 g/t Au over 1.50 metres
approximately 100 metres below the final historic mining stope (Figure 1). This serves to demonstrate
the continuity of mineralization from the former mine downwards towards the cluster previously published
wedges (Figures 1 & 2; see
Radisson news release dated July 16, 2025
). Current drilling in this area is
focussed on infilling with pilot holes and wedge extensions both above and below the OB-24-337 pattern
of wedge branches to test the full continuity of mineralization from the historic mine down to 2 kilometres
depth.
Step-out drilling with wedge branches has also confirmed high-grade mineralization 170 metres below
the base of the existing mineral resources at Trend #1 and 300 metres at Trend #2. These have included
pilot hole OB-24-324, which intersected 27.61 g/t Au over 6.0 metres at Trend #1 (see
Radisson news
release dated October 30, 2024
) and OB-24-363, which intersected 8.41 g/t Au over 2.20 metres,
including 14.40 g/t Au over 1.20 metres
and
9.07 g/t Au over 1.80 metres, including 12.10 g/t Au over
0.90 metres at Trend #2 (see
Radisson news release dated September 8, 2025
). Today's results
include six wedges from drill hole OB-25-371, which demonstrate strongly developed, high-grade
mineralization on the western edge of the deep extension of Trend #2. These holes include OB-25-
371W5, which intersected 10.50 g/t Au over 6.5 metres, including 14.90 g/t Au over 1.5 metres and
including 16.95 g/t Au over 1.0 metre (Figures 1&3). The significance of these holes is that the apparent
separation of Trend #1 and Trend #2 is based, in part, on a data gap caused by drill rig access
restrictions and a lack of drilling (Figure 2). Targeting this gap and testing for continuity of mineralization
between Trends #1 and #2, as well as at depth, is a priority of the current drill program.
Today's results also include the first drill holes located below the western portion of the historic O'Brien
Gold Mine, designated "O'Brien Mine West". As with the main mining area, no exploration had been
conducted below O'Brien Mine West since operations ended in 1957. From pilot hole OB-25-376 and
wedge branches W1 to W5, five holes returned intercepts with grades and thicknesses consistent with
the Project's mineral resources, including OB-25-376W1, which intersected 9.16 g/t Au over 2.5 metres,
including 14.70 g/t Au over 1.1 metres (Figure 1). This now extends gold mineralization at O'Brien Mine
West 160 metres below the base of the former mine workings (Figure 4).
Figure 3
: Vertical Cross Section through "Trend #2" with Drill Hole Wedges OB-25-371W2 to W6
To view an enhanced version of this graphic, please visit:
https://images.newsfilecorp.com/files/10977/272164_3fafb92ae4c30b1d_005full.jpg
Figure 4
: Vertical Cross Section through "O'Brien Mine West" with Drill Hole OB-25-376 and Wedges
W1 to W5
To view an enhanced version of this graphic, please visit:
https://images.newsfilecorp.com/files/10977/272164_3fafb92ae4c30b1d_006full.jpg
Table 2
: Detailed Assay Results (see "Notes on Calculation of Drill Intercepts")
DDH
Zone
From (m)
To (m)
Core Length (m)
Au g/t - Uncut
Host Lithology
1,321.0
1,322.0
1.00
1.76
PON-S3
1,487.7
1,488.7
1.00
2.02
POR-S
1,495.3
1,496.3
1.00
1.06
POR-S
OB-24-337W8
O'Brien Mine
1,529.0
1,530.5
1.50
5.33
S1p
1,536.7
1,537.7
1.00
1.20
S1p
1,556.5
1,558.0
1.50
1.66
S1p
1,605.8
1,607.8
2.00
3.25
ZFLLC
OB-24-337W9
O'Brien Mine
1,381.0
1,383.0
2.00
2.12
PON-S3
Including
1,381.0
1,382.0
1.00
3.12
PON-S3
1,597.5
1,599.0
1.50
1.10
POR-S
1,604.0
1,605.5
1.50
1.35
POR-S
1,634.0
1,635.2
1.20
1.37
V3-CEN
1,650.0
1,651.5
1.50
2.94
V3-CEN
1,664.0
1,667.0
3.00
1.30
S1p
1,688.0
1,689.5
1.50
2.73
S1p
1,733.0
1,734.0
1.00
1.81
V3-N
1,794.0
1,797.0
3.00
1.16
V3-N
OB-24-337W10
O'Brien Mine
870.0
871.5
1.50
5.24
PON-S3
877.5
879.0
1.50
4.86
PON-S3
1,238.0
1,243.5
5.50
1.71
V3-S
1,248.0
1,250.0
2.00
2.53
POR-S
1,270.0
1,273.5
3.50
2.16
POR-S
Including
1,270.0
1,271.0
1.00
4.93
POR-S
OB-24-337W11
O'Brien Mine
856.0
857.5
1.50
1.48
PON-S3
1,221.0
1,222.5
1.50
5.46
V3-S
1,241.0
1,244.0
3.00
1.99
V3-S
1,258.5
1,260.0
1.50
1.38
POR-S
1,271.5
1,274.5
3.00
7.00
V3-CEN
Including
1,273.0
1,274.5
1.50
12.60
V3-CEN
1,305.1
1,306.6
1.50
13.00
POR-N
1,312.5
1,315.5
3.00
3.00
V3-N
Including
1,314.0
1,315.5
1.50
4.66
V3-N
OB-25-371W2
Trend #2
1,166.5
1,168.0
1.50
1.23
V3-S
1,188.2
1,189.5
1.30
5.63
V3-S
1,251.0
1,252.5
1.50
7.18
V3-S
1,261.0
1,264.0
3.00
1.77
V3-S
1,268.5
1,270.0
1.50
1.26
POR-S
OB-25-371W3
Trend #2
1,000.5
1,001.5
1.00
2.14
PON-S3
1,183.0
1,184.0
1.00
1.77
V3-S
1,266.2
1,267.5
1.30
2.19
V3-N
OB-25-371W4
Trend #2
1,081.5
1,082.5
1.00
1.57
V3-S
1,086.0
1,094.3
8.30
2.19
V3-S
Including
1,086.0
1,087.5
1.50
4.04
V3-S
1,110.0
1,111.0
1.00
7.63
V3-S
1,139.5
1,142.0
2.50
11.25
V3-S
Including
1,139.5
1,141.0
1.50
17.80
V3-S
1,150.0
1,151.5
1.50
1.35
POR-S
1,166.5
1,167.5
1.00
1.90
POR-S
1,196.0
1,197.5
1.50
2.29
V3-N
OB-25-371W5
Trend #2
903.0
904.0
1.00
2.54
PON-S3
1,123.5
1,125.0
1.50
2.06
V3-S
1,140.0
1,141.0
1.00
1.70
V3-S
1,155.5
1,157.5
2.00
2.19
V3-S
1,158.7
1,165.2
6.50
10.50
V3-S
Including
1,160.0
1,161.5
1.50
14.90
V3-S
Including
1,163.0
1,164.0
1.00
16.95
V3-S
1,180.0
1,183.0
3.00
2.43
V3-S
1,196.5
1,198.0
1.50
2.08
V3-S
1,210.0
1,211.5
1.50
1.05
V3-S
1,221.0
1,237.0
16.00
1.64
POR-S
Including
1,228.5
1,230.0
1.50
4.75
POR-S
1,248.0
1,249.5
1.50
2.50
S1p
1,260.0
1,261.2
1.20
1.06
S1p
OB-25-371W6
Trend #2
943.8
945.2
1.40
1.30
PON-S3
1,071.0
1,080.0
9.00
4.51
V3-S
Including
1,072.5
1,074.0
1.50
10.70
V3-S
1,102.0
1,104.5
2.50
2.81
POR-S/V3-CEN
Including
1,103.0
1,104.5
1.50
3.67
POR-S/V3-CEN
1,112.0
1,114.9
2.90
2.06
V3-CEN
OB-25-376
O'Brien Mine West
544.5
547.0
2.50
8.05
PON-S3
Including
544.5
545.5
1.00
15.75
PON-S3
1,068.0
1,069.5
1.50
4.22
POR-S
1,091.0
1,092.5
1.50
6.97
V3-CEN
1,117.0
1,118.0
1.00
1.20
S1p
1,144.0
1,147.0
3.00
3.71
POR-N
1,061.0
1,062.5
1.50
1.34
V3-CEN
OB-25-376W1
O'Brien Mine West
1,065.6
1,068.1
2.50
9.16
S1p
Including
1,067.0
1,068.1
1.10
14.70
S1P
1,093.0
1,094.0
1.00
2.63
S1p
OB-25-376W2
O'Brien Mine West
1,009.7
1,011.0
1.30
1.09
POR-S
1,076.3
1,077.5
1.20
7.02
S1p
OB-25-376W3
O'Brien Mine West
932.6
934.0
1.40
2.10
POR-S
979.5
981.0
1.50
1.17
S1p
989.5
990.5
1.00
5.19
S1p
992.0
993.5
1.50
1.03
S1p
1,023.0
1,024.5
1.50
1.03
S3p
OB-25-376W4
O'Brien Mine West
944.5
947.0
2.50
1.55
V3-S/POR_S
986.5
989.0
2.50
1.69
POR-N/S1p
992.0
995.0
3.00
1.44
S1p
1,000.5
1,001.5
1.00
2.66
S1p
OB-25-376W5
O'Brien Mine West
1,040.0
1,041.5
1.50
1.10
V3-CEN
1,059.5
1,062.0
2.50
3.55
V3-CEN/S1p
1,094.5
1,096.0
1.50
3.98
S1p
Table 3
: Drill Hole Collar Information for Holes contained in this News Release
DDH
Zone
Easting
Northing
Azimuth
Dip
Hole Length (m)
OB-24-337W8
O'Brien Mine
693700
5345070
346
-79.5
638
OB-24-337W9
O'Brien Mine
693700
5345070
346
-79.5
614
OB-24-337W10
O'Brien Mine
693700
5345070
346
-79.5
610
OB-24-337W11
O'Brien Mine
693700
5345070
346
-79.5
656
OB-25-371W2
Trend #2
694531
5345147
1
-71.0
446
OB-25-371W3
Trend #2
694531
5345147
334
-82.0
691
OB-25-371W4
Trend #2
694531
5345147
334
-82.0
524
OB-25-371W5
Trend #2
694531
5345147
334
-82.0
525
OB-25-371W6
Trend #2
694531
5345147
334
-82.0
354
OB-25-376
O'Brien Mine West
693100
5345148
347
-78.5
1196
OB-25-376W1
O'Brien Mine West
693100
5345148
347
-78.5
362
OB-25-376W2
O'Brien Mine West
693100
5345148
347
-78.5
446
OB-25-376W3
O'Brien Mine West
693100
5345148
347
-78.5
488
OB-25-376W4
O'Brien Mine West
693100
5345148
347
-78.5
530
OB-25-376W5
O'Brien Mine West
693100
5345148
347
-78.5
583
Notes:
Hole lengths for wedges represent meterage from point of wedge. Drill hole OB-24-337 was completed in 2024 while its wedge branches were
drilled in 2025.
QA/QC
All drill cores in this campaign are NQ in size. Assays were completed on sawn half-cores, with the
second half kept for future reference. The samples were analyzed using standard fire assay procedures
with Atomic Absorption (AA) finish at ALS Laboratory Ltd, in Val-d'Or, Quebec. Samples yielding a
grade higher than 10 g/t Au were analyzed a second time by fire assay with gravimetric finish at the
same laboratory. Mineralized zones containing visible gold were analyzed with metallic sieve procedure.
Standard reference materials, blank samples and duplicates were inserted prior to shipment for quality
assurance and quality control (QA/QC) program.
Qualified Persons
Disclosure of a scientific or technical nature in this news release was prepared under the supervision of
Mr. Richard Nieminen, P.Geo, (QC), a geological consultant for Radisson and a Qualified Person for
purposes of NI 43-101. Mr. Luke Evans, M.Sc., P.Eng., ing, of SLR Consulting (Canada) Ltd., is the
Qualified Person responsible for the preparation of the MRE at O'Brien. Each of Mr. Nieminen and Mr.
Evans is independent of Radisson and the O'Brien Gold Project.
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