ATHA Energy Confirms Multiple High-Grade Discoveries Along the Mineralized Rib Corridor at Angilak Project – Assays from Rib East, WEST, and South Discoveries – All Holes Intersecting Uranium Mineralization, Grades up to
ATHA ENERGY CONFIRMS MULTIPLE HIGH-GRADE DISCOVERIES
ALONG THE MINERALIZED RIB CORRIDOR AT ANGILAK PROJECT –
ASSAYS FROM RIB EAST, WEST, AND SOUTH DISCOVERIES – ALL
HOLES INTERSECTING URANIUM MINERALIZATION, GRADES UP TO
5.55% U3O8
HIGHLIGHTS
• Assays confirm uranium mineralization across the Mineralized RIB Corridor (“MRC”) at RIB
South, East and West Discoveries, where results from twelve drillholes intersected uranium
mineralization (Figures 2 & 3). These results are in addition to the previously announced RIB
North Discovery, where the maiden drillhole, RIBN-DD-001, returned assays with 34.7 m of
total composite uranium mineralization1, including 13.6 m grading 0.53% U₃O₈, 1.1 m
grading 4.81% U₃O₈, and grades up to 8.16% U₃O₈ over 0.5 m (See November 20th, 2025, RIB
North Assay Release);
RIB East Discovery
• Located on the 4.5 km long Eastern Limb of the MRC , ~1.4 km south of the significant RIB
North Discovery (Figures 2 & 3);
• Currently defined by eight diamond drillholes over a 750 m strike length that remains open
in all directions, with drilling highlighted by:
o RIBE-DD-003 assays returned total composite uranium mineralization 1 of 8.6 m
encompassing four zones from 101.4 m to 374.1 m (Figure 4), including a high-grade
intersection2 from 276.2 m to 277.3 m with 2.69% U3O8 over 1.1 m, including 5.55%
U3O8 over 0.5 m;
o RIBE-DD-007 assays returned total composite uranium mineralization 1 of 8.7 m
encompassing six zones from 174.0 m to 215.3 m (Figure 5), including a higher-grade
intersection from 207.2 m to 211.3 m with 0.236% U3O8 over 4.1 m, including 1.15%
U3O8 over 0.5 m;
RIB West Discovery
• Located on the 4.0 km long Western Limb of the MRC, ~1.8 km southwest of the significant
RIB North Discovery (Figures 2 & 3);
• Currently defined by three diamond drillholes over a 2.2 km strike length that remains open
in all directions, with drilling highlighted by:
o RIBW-DD-001 assays returned total composite uranium mineralization 1 of 1.7 m
from 393.5 m to 395.2 m (Figure 6) with an average grade of 0.78% U3O8, including
a high-grade intersection2 with 1.36% U3O8 over 0.6 m;
o RIBW-DD-003 assays returned total composite uranium mineralization 1 of 2.0 m
from 234.2 m to 236.2 m (Figure 7) with an average grade of 0.291% U3O8, including
a high-grade intersection2 of 1.07% U3O8 over 0.5 m;
RIB South Discovery
• Located on the 4. 5 km long Eastern Limb of the MRC, ~ 2.25 km south of the RIB East
Discovery (Figures 2 & 3);
• Currently defined by one diamond drillhole , with pros pective strike length open and
untested in all directions along the MRC, with drilling highlighted by:
o RIBS-DD-001 assays returned total composite uranium mineralization 1 of 2.0 m
encompassing two zones from 158.5 m to 252.1 m (Figure 8), including 1.5 m from
250.6 m to 252.1 m with an average grade of 0.11% U3O8;
Mineralized RIB Corridor
• Mineralized RIB Corridor – 12 km corridor containing stacked graphitic shear zones ,
identified using 3D EM Inversion modeling. During the 2025 Angilak Exploration Program
these EM anomalies were drill tested, resulting in a 100% success rate of intersecting
uranium mineralization associated with graphitic shear zones, and the discovery of four new
mineralized areas: RIB East, West, North and South, in addition to the historic RIB Discovery3
(Figures 2 & 3);
• Uranium mineralization discovered along the MRC consists of Athabasca styles of
mineralization including basement, sandstone, and unconformity hosted mineralization;
• The MRC remains open within all discovery areas and is currently constrained only by a lack
of additional MMT survey data south of the Historic RIB Discovery. Additional MMT surveys
paired with 3D EM Inversion modeling is planned for 2026, designed to unlock and define
the true scale and significance of the MRC and the entirety of the Angikuni Basin;
• Additional drill core samples from the KU Discovery, Mushroom Lake, and the Lac 50 Deposit
area have been submitted to the Saskatchewan Research Council (SRC) Geoanalytical
Laboratory for analysis. The Company anticipates disclosing all remaining assay results in
the coming weeks.
Troy Boisjoli, CEO commented: ”Since acquiring the Angilak Uranium Project in 2024 ATHA has
completed two successful drill campaigns comprising 46 holes across the Lac 50 Deposit and RIB -Nine
Iron trends – 45 of those holes have intersected uranium mineralization. The 2024 Angilak Exploration
Program focused on the Lac 50 Deposit Trend, testing the envelop o f mineralization with large step
outs, culminating in release of an Exploration Target for the Lac 50 Deposit area – which remains
completely open and unconstrained.
During the 2025 Program, our goal was to start to unlock the regional potential of Angilak . Testing
new targets which had been derisked through our systematic exploration approach, utilizing all the
tools at our disposal to drill test in the most cost -effective means possible. The assay results from the
Mineralized RIB Corridor, hitting uranium mineralization on 100% of the holes drilled along the 12-km
MRC speaks for itself. The success we’ve had at RIB demonstrates to us that the scale of the MRC is
something truly special, and may represent one of the most significant emerging uranium regions in
Canada.”
Cliff Revering, VP Exploration added : “The Mineralized RIB Corridor continues to deliver compelling
results, supported by the latest confirmation assays from the 2025 exploration program. Uranium
mineralization encountered to date , spanning a 12 km structural corridor and anchored by the RIB
North Discovery , demonstrates both scale and high-grade potential . Combined with the positive
geological and geochemical signatures emerging from our 2025 work, the data increasingly points to
a large mineralizing system.
Since acquiring the Angilak Project in 2024, ATHA’s disciplined exploration strategy has consistently
advanced discovery within the Angikuni Basin , leveraging targeted exploration tools that enhance
efficiency and reduce risk of discovery. The delineation of the Mineralized RIB Corridor within the larger
RIB–Nine Iron regional trend represents a significant new development and highlights just one of
several high-upside targets across the basin.
As we look ahead to 2026, ATHA is well-positioned to build on this momentum. Our objective remains
clear: to continue unlocking the value of this emerging uranium district and to demonstrate the long-
term growth potential of the Angikuni Basin.”
Vancouver, British Columbia , December 10th, 2025 – ATHA Energy Corp. (TSX.V: SASK) (FRA: X5U)
(OTCQB: SASKF) (“ATHA” or the “Company”), is pleased to announce assay results from the remaining
twelve holes drilled along the Mineralized RIB Corridor (“MRC”), completed as part of the 2025 Angilak
Exploration Program at its 100%-owned Angilak Uranium Project in Nunavut, Canada (Figure 1). Assay
results confirm uranium mineralization was intersected in all drillholes along the 12 km MRC, including
the RIB East, West, and South Discoveries , in addition to the previously ann ounced RIB North
Discovery.
At the RIB East Discovery, a total of eight diamond drillholes were completed across a total strike
length of 750 m and the area remains open in all directions. Drilling at RIB East is highlighted by RIBE-
DD-003, assays returned total composite uranium mineralization 1 of 8.6 m encompassing four zones
from 101.4 m to 374.1 m (Figure 4). This includes a high-grade2 intersection from 276.2 m to 277.3 m
with results returning an average grade of 2.69% U3O8 over 1.1 m, including 5.55% U3O8 over 0.5 m. At
the RIB West Discovery, a total of three diamond drillholes were completed across a 2.2 km strike
length, with the area remains open in all directions. Drilling at RIB West is highlighted by RIBW-DD-
001 which returned total composite uranium mineralization1 of 1.7 m from 393.5 m to 395.2 m (Figure
6) with an average grade of 0.78% U3O8, including a high -grade2 intersection of 1.36% U3O8 over 0.6
m. RIB South is currently defined by one diamond drillhole, located ~ 2.25 km to the south of the RIB
East Discovery . RIBS-DD-001 intersected total composite uranium mineralization 1 of 2.0 m
encompassing two zones from 158.5 m to 252.1 m (Figure 8), including 1.5 m from 250.6 m to 252.1
m with an average grade of 0.11% U3O8.
The Mineralized RIB Corridor is a 12 km long corridor containing stacked graphitic shear zones ,
identified using 3D EM Inversion modeling. During the 2025 Angilak Exploration Program these EM
anomalies were drill tested, resulting in a 100% success rate of intersecting uranium mineralization
associated with the graphitic shear zones , and the discovery of four new mineralized areas: RIB East,
West, North and South, in addition to the historic RIB Discovery 3 (Figures 2 & 3). Uranium
mineralization discovered along the MRC consists of Athabasca style mineralization including
basement, sandstone, and unconformity hosted. The MRC remains open in all directions within the
discovery areas with additional prospective strike length constrained only by a lack of additional MMT
survey data south of the Historic RIB Discovery. Additional MMT surveys paired with 3D EM Inversion
modeling is planned for 2026, designed to unlock and define the true scale and significance of the
MRC and the entirety of the Angikuni Basin.
Detailed lithologic striplogs, including assay results tables, for all twelve holes can viewed in the
Supplementary Release on ATHA Energy’s website (Striplog Data).
Figure 1: Angilak Project Area – 2025 Exploration Target Area (Black Rectangles), Mineralized RIB Corridor (Red
Rectangle), & Mapped Historic Mineralized Showings
Figure 2: 2025 Angilak Exploration Program – EM Inversion Model & Drill Collar Locations from MRC, along the
RIB-Nine Iron Trend.
Figure 3: 2025 Angilak Exploration Program – Isometric schematic of the MRC, displaying EM Inversion model
and 2025 drilling.
Table 1: 2025 Angilak Exploration Program Drill Collar Information
Hole ID Trend Zone Azimuth
(°)
Dip
(°)
Easting
(mE)
Northing
(mN)
Elevation
(m)
Final Depth
(m)
*KU-DD-
001
RIB-Nine
Iron
KU
Target 30 70 515830 6936190 256.5 599
*J4R-DD-
091 Lac 50 J4/Ray 25 57 522295 6938558 218 650
*RIBE-DD-
001
RIB-Nine
Iron
RIB
East 145 -55 497928 6929449 270 443
*RIBE-DD-
002
RIB-Nine
Iron
RIB
East 145 -55 497766 6929322 271 345
*RIBE-DD-
003
RIB-Nine
Iron
RIB
East 145 -63 497524 6929337 271 398
*RIBE-DD-
004
RIB-Nine
Iron
RIB
East 145 -60 497404 6920180 271 428
*RIBE-DD-
005
RIB-Nine
Iron
RIB
East 155 -65 497530 6929401 270 472
*RIBE-DD-
006
RIB-Nine
Iron
RIB
East 145 -60 497670 6929501 273 491
*RIBE-DD-
007
RIB-Nine
Iron
RIB
East 325 -50 497798 6929101 274 467
*RIBE-DD-
008
RIB-Nine
Iron
RIB
East 325 -55 498284 6929287 264 464
*RIBW-DD-
001
RIB-Nine
Iron
RIB
West 150 -50 495831 6929490 274 503
*RIBW-DD-
002
RIB-Nine
Iron
RIB
West 145 -55 497766 6929322 271 380
*RIBW-DD-
003
RIB-Nine
Iron
RIB
West 325 -55 497645 6930031 275 347
*RIBN-DD-
001
RIB-Nine
Iron
RIB
North 300 -65 499574 6929887 261 623
*RIBS-DD-
001
RIB-Nine
Iron
RIB
South 150 -50 495747 6927640 277.5 377
*KU-DD-
002
RIB-Nine
Iron
KU
Target 30 -70 515525 6936210 251 616
*KU-DD-
003
RIB-Nine
Iron
KU
Target 30 -70 515758 6936059 268.5 56
*KU-DD-
003A
RIB-Nine
Iron
KU
Target 30 -68 515758 6936059 268.5 605
*KU-DD-
004
RIB-Nine
Iron
KU
Target 30 -60 515757 695641 255 602
*KU-DD-
005
RIB-Nine
Iron
KU
Target 210 -70 515980 6935734 256 302
*KU-DD-
006
RIB-Nine
Iron
KU
Target 30 -70 514794 6935805 275 647
*ML-DD-
013 Lac 50 ML
Target 25 -50 523968 6939404 215 551
*ML-DD-
014 Lac 50 ML
Target 25 -50 524869 6939109 206 407
*Previously released drillholes from 2025 Angilak Exploration Program
Figure 4: Striplog RIBE-DD-003 showing mineralized interval with composite uranium mineralization1 with
average grades – derived from assay samples.
Figure 5: Striplog RIBE-DD-007 showing mineralized interval with composite uranium mineralization1 with
average grades – derived from assay samples.