Canstar Resources Intersects 15.6 Metres of Massive Sulphide Grading 2.3% CuEq at Mary March, Including 9.75 Metres at 3.3% CuEq All Four Phase 1 Holes Intersect Mineralization
NEWS RELEASE
Canstar Resources Intersects 15.6 Metres of Massive Sulphide Grading 2.3% CuEq
at Mary March, Including 9.75 Metres at 3.3% CuEq
All Four Phase 1 Holes Intersect Mineralization
Toronto, Ontario – August 27, 2026 – Canstar Resources Inc. (TSXV: ROX; OTCID: CSRNF) (“Canstar” or the
“Company”) today reported results from the first phase of its 2026 drill program, including the widest
massive sulphide intercept in the drilling record of its Mary March Project in the Buchans district of central
Newfoundland: 15.6 metres (“m”) grading 2.3% copper equivalent (“CuEq”)¹ starting at a downhole depth of
467.4 m in drill hole MM-26-42, including 9.75 m at 3.3% CuEq¹. The reported interval is a downhole length
through fault-bounded massive sulphide (rock logged at greater than 50% sulphide minerals) hosted by a
rhyolite flow-dome, designated the Fleetway Rhyolite; its full width was not intersected. The mineralization
remains open along strike and at depth.
All four holes of the 2026 summer drill program intersected visually logged mineralization typical of a
volcanogenic massive sulphide (“VMS”) system, close to the depths anticipated by the Company’s geological
model, which will guide the placement of future drill holes. Drill holes MM-26-41, MM-26-43 and MM-26-44
were the first to pierce the full thickness of the Fleetway Rhyolite, with apparent thickness ranging from 298
to 320 m. Across the program, massive sulphide was intersected in two holes (the second visually logged,
with assays pending²), and most of the host unit remains untested.
As announced on July 21, 2026, earn-in partner VMS Mining Corporation (“VMSC”) invested an additional
$2.0 million ahead of schedule, bringing total funding to $4.0 million to date, including $3.5 million in 2026.
VMSC’s advance funds a planned fall drill campaign, which remains subject to drill-rig availability and other
operational considerations. The program follows more than a year of systematic targeting work led by Dr.
Harold Gibson, Vice President, Exploration of VMSC, with input from Dr. Rodney Allen, Volcanic Resources
AB and former Chief Geologist of Boliden, on the re-logging of historic core and comparisons to the Buchans
host rocks.
Highlights
• Widest massive sulphide intercept in the Project’s drilling record: Drill hole MM-26-42 intersected 15.6
m of massive sulphide grading 2.3% CuEq¹ (0.73% copper, 0.73% lead, 2.10% zinc, 0.71 grams per tonne
(“g/t”) gold and 19.0 g/t silver). The interval, a core length rather than true thickness, occurs 60 m below
the upper contact of the rhyolite and lies approximately 100 m along strike from the previously reported
1999 discovery intercept⁴.
• Including 9.75 m at 3.3% CuEq¹ (1.13% copper, 1.14% lead, 3.27% zinc, 0.89 g/t gold and 25.5 g/t
silver), which includes 5.0 m at 3.9% CuEq¹ (1.71% copper, 1.11% lead, 3.02% zinc, 0.94 g/t gold and
32.6 g/t silver).
• The hole was stopped by unstable ground conditions associated with a fault zone at approximately
576 m, before reaching the lower rhyolite contact, which remains untested at this location. Assays
are pending for a discrete 1 m visually logged massive sulphide interval 19 m below the main
assayed interval².
• Massive sulphide intersected in a second hole: Drill hole MM-26-44 intersected two narrow
intervals of visually logged massive sulphide, with zinc and copper sulphide minerals, at the upper
rhyolite contact (330.7–331.9 m and 332.2–333.8 m; approximately 2.8 m combined; assays
pending²). The hole also intersected strongly altered, pyritic mafic breccias at the lower rhyolite
contact (632.5 m). VMS systems may form more than one massive sulphide lens within a host
rhyolite.
• Interpreted potential VMS feeder zone identified: Drill hole MM-26-41 encountered copper- and
zinc-bearing stringer and disseminated mineralization in multiple intervals totalling approximately
271 m of altered rhyolite, strongest over the upper 118 m, interpreted as a potential VMS feeder
zone, the conduit beneath a massive sulphide lens (reported July 8, 2026)³; assays pending. Below
the lower rhyolite contact at 710.6 m, mafic breccias carry an 8 m interval of stringer mineralization
containing chalcopyrite and sphalerite (assays pending).
• Step-out hole extends mineralized area: Drill hole MM-26-43 intersected the upper rhyolite contact
at 478 m, approximately 130 m from hole MM-26-42 (100 m deeper and 75 m to the southwest),
extending the altered rhyolite to the southwest; the faulted contact lies within a 17 m interval of
visually logged moderate mineralization, and altered rhyolite continues to 676 m. Assays pending².
• Further drill results and drilling anticipated: Assay results are expected through September.
Borehole electromagnetic (“BHEM”) surveying of all four PVC-cased holes, which can detect
conductive massive sulphide beyond the drill holes, is expected to begin mid-September. Planning is
underway to secure a drill rig for a fall program targeted to begin in October, pending drill-rig
availability and other operational considerations.
• Mary March project ownership consolidated: Glencore’s legacy joint-venture interest in Mary
March converted to a 2% net smelter returns royalty, consolidating Project ownership under Canstar
and VMSC.
Juan Carlos Giron Jr., President & CEO of Canstar, commented: “We are encouraged to have
intersected the widest massive sulphide interval in Mary March’s drilling record, in the first holes drilled
here since 2019, and to have found it where our geological model predicted it. Buchans is a historically
productive VMS district: the camp, just 20 km from us, produced some of the highest-grade VMS ore
mined in North American history⁵, and Mary March has comparable host rocks. VMSC’s accelerated $2.0
million investment supports the next phase of work, and the planned fall campaign will continue testing
the system.”
Bob Patey, P.Geo., Vice President, Exploration, commented: “This drill program began testing the
rhyolite systematically, including, for the first time, its far southeastern margin and its base. This second
notable massive sulphide intercept at Mary March may indicate a significant mineralized system, subject
to further drilling and assay confirmation. VMS systems can form multiple massive sulphide lenses
stacked through the target rhyolite interval, and we believe that internal contacts within the Fleetway
Rhyolite and its lower contact warrant further testing, guided by our systematic targeting approach.”
Assay Results and Interpretation
VMS deposits form from sea-floor hydrothermal systems and can occur within a host rhyolite and at its
margins, commonly as more than one lens. The massive sulphide mineralization in MM-26-42 is
bounded by faults, and the Project’s historic discovery intercept, known as the Mary March intercept
(9.63 m grading 10.1% zinc, 1.8% lead, 0.64% copper, 122 g/t silver and 4.2 g/t gold, 1999)⁴,
approximately 100 m along strike to the northeast, is likewise fault-bounded. These intercepts may not
reflect the complete width of the original massive sulphide lens or lenses. Because the Mary March
sequence has been folded and faulted, the position of these intercepts within the original mineralizing
system cannot yet be determined, and no inference is drawn from the differing metal contents of the
two intercepts.
Drill holes MM-26-41, MM-26-43 and MM-26-44 each pierced the entire rhyolite package, which
measures approximately 298 to 320 m in apparent thickness where pierced, including approximately
302 m in MM-26-44, updating the approximately 250 m previously reported³. Most of the Fleetway
Rhyolite, including the lower contact below MM-26-42, remains prospective and has not yet been drill-
tested. Based on limited drilling so far, the mineralized system is open along strike and at depth and
requires further drilling to assess its extent.
Reported intervals are downhole lengths. The true thickness of the mineralized material that was
intersected is interpreted to be less than the downhole lengths of the intervals, and the full width of the
original fault-bounded massive sulphide has not been determined; both will require further drilling.¹ The
Company is not estimating the dimensions of any mineralized body based on current drill results.
Table 1: MM-26-42 composite assay results
Interval From (m) To (m) Length (m) Cu % Pb % Zn % Au g/t Ag g/t CuEq %¹
Massive sulphide interval 467.4 483.0 15.6 0.73 0.73 2.10 0.71 19.0 2.3
including 473.25 483.0 9.75 1.13 1.14 3.27 0.89 25.5 3.3
including 476.0 481.0 5.0 1.71 1.11 3.02 0.94 32.6 3.9
Table 2: MM-26-42 sample-by-sample assay results
Sample From (m) To (m) Length (m) Cu % Pb % Zn % Au g/t Ag g/t
378841 467.4 469.0 1.6 0.07 0.09 0.33 0.34 9.7
378842 469.0 470.0 1.0 0.10 0.01 0.19 0.34 6.1
378843 470.0 471.0 1.0 0.07 0.01 0.09 0.42 6.6
378827 471.0 472.0 1.0 0.02 0.03 0.05 0.55 11.1
378828 472.0 473.25 1.25 0.03 0.03 0.08 0.50 6.5
378829 473.25 474.0 0.75 0.39 1.04 4.63 0.71 11.3
378830 474.0 475.0 1.0 0.98 1.59 4.40 0.98 21.2
378831 475.0 476.0 1.0 0.66 2.53 6.53 1.61 34.3
378832 476.0 477.0 1.0 1.66 1.40 4.41 1.13 36.7
378833 477.0 478.0 1.0 2.03 1.85 3.76 1.19 47.6
378834 478.0 479.0 1.0 2.74 0.34 0.69 0.76 34.3
378835 479.0 481.0 2.0 1.05 0.97 3.13 0.82 22.2
378836 481.0 482.0 1.0 0.33 0.50 1.56 0.43 13.1
378837 482.0 483.0 1.0 0.18 0.19 0.78 0.37 9.0
Table 3: Visually logged massive sulphide, assays pending
Hole From (m) To (m) Length (m) Status
MM-26-42 501.8 502.8 1.0 Visually logged massive sulphide interval, with assays pending²
MM-26-44 330.7 331.9 1.2 Visually logged massive sulphide interval, with assays pending²
MM-26-44 332.2 333.8 1.6 Visually logged massive sulphide interval, with assays pending²
Quality Assurance / Quality Control (“QA/QC”)
Samples of sawn half core were prepared at the Canstar core shed facility in Millertown, Newfoundland
and Labrador, packed in bags secured with heavy-duty, tamper-evident plastic seals, and shipped by
commercial carrier to ALS in Moncton, New Brunswick. ALS Canada Ltd. is independent of Canstar and is
accredited to ISO/IEC 17025:2017 and certified to ISO 9001:2015. Certified reference materials,
consisting of four reference standards and two blanks, were inserted within every 100 samples. Samples
were analyzed using a four-acid digestion package (ME-4ACD81), and samples assaying over 10,000
parts per million (“ppm”) silver, copper, lead or zinc were re-run using an over-limit method for that
element (Ag-OG62, Cu-OG62, Pb-OG62, Zn-OG62). Gold was analyzed using a 30 g fire assay with an
atomic absorption finish (Au-AA25). The Company’s Qualified Person (“QP”) compared the analytical
results of the reference materials to the accepted values, confirming acceptable accuracy of the analysis.
Table 4: Drill hole collar details
Hole ID Easting Northing Elevation (m) Azimuth Dip Depth (m)
MM-26-41 534419 5408974 188 145.52 -47.9 757.0
MM-26-42 534326 5408892 191 140.5 -68.31 576.0
MM-26-43 534283 5408843 193 136.58 -57.75 745.0
MM-26-44 534326 5408892 191 133.04 -58.98 678.0
Collar coordinates are NAD27, UTM Zone 21N; negative dips denote downward inclination. MM-26-42
and MM-26-44 were drilled from the same pad. Program total: 2,756 m in four holes.
Beyond the Priority Target
The Fleetway Rhyolite is the Company’s priority target at Mary March, which has multiple prospective
areas; government research describes the Mary March alteration system as among the most significant
reported in the region⁶. Approximately 1.8 kilometres northeast of the current drill holes, 2019
trenching discovered, in bedrock, massive sulphide clasts in a debris-flow unit with grab samples
returning up to 5.7% copper⁷. Transported sulphide clasts of this kind also formed part of the historically
mined Buchans ores⁵. The source of the sulphide clasts has not been located. The Nancy April zone hosts
footwall zinc mineralization in historic drill hole MM-294-03, which intersected 20.6 m grading 0.13%
Cu, 1.08% Pb, 3.02% Zn and 3.43 g/t Ag⁴. A discrete chargeability anomaly located more than 600 m to
the northwest of the Nancy April zone, as observed within the Company’s recent induced polarization
(“IP”) survey, has yet to be drill-tested.
Ownership Consolidated: Glencore Legacy Interest Converted to Royalty
Canstar also announces that the legacy joint-venture interest of Glencore Canada Corporation
(“Glencore”) in a portion of the Mary March property has been converted into a 2% net smelter returns
royalty. The conversion consolidates the Project’s ownership structure under Canstar and its earn-in
partner VMSC, resolving a legacy arrangement that predated the Company’s current programs.
Next Steps
• Assay results for drill holes MM-26-41, MM-26-43 and MM-26-44, along with the remaining MM-26-
42 samples, are expected through September.
• BHEM surveys of all four PVC-cased holes are expected to begin mid-September and will test for off-
hole conductors to refine targets for the fall campaign.
• The fall drill campaign under the joint venture with VMSC is currently being planned; planning is
underway to secure a drill rig, with drilling targeted to begin in October, subject to drill-rig
availability and other operational considerations.
The Company will provide further updates on its 2026 drilling campaign as it progresses.
Qualified Person
Bob Patey, B.Sc. (Hons.), P.Geo., Vice President, Exploration of Canstar and a Qualified Person as defined
in National Instrument 43-101 – Standards of Disclosure for Mineral Projects (“NI 43-101”), has reviewed
and approved the scientific and technical information disclosed in this news release, and has verified
that the 15.6 m interval in drill hole MM-26-42 is the widest massive sulphide intercept in the Project’s
drilling record.
Figures
Figure 1: Mary March Project in the Buchans VMS district, approximately 20 km from the historic Buchans mine.
Figure 2: Mary March prospectivity map. Drill traces and the rhyolite outline are projected to surface: the 2026 holes intersected
the rhyolite’s southeast margin at depth, and that contact is projected to surface here. Chargeability anomalies are geophysical
model shapes, not mineralization outlines. Grades are shown where assays have been received.
Figure 3: Three-dimensional geological model of the Mary March area, viewed toward the southwest. Drill holes are shown in
their true relative positions; no scale applies to this oblique view. Rhyolite host (yellow); direct current induced polarization
(“DCIP”) chargeability model surface (orange; a geophysical model shape, not a mineralization outline); historic drill holes
(black); 2026 drill holes (red traces, labelled in blue); stars mark massive sulphide intersections. Intervals are downhole lengths;
historical intercepts per note 4.
Copper-equivalent grades shown in the figures are calculated using the formula, metal prices and assumptions described in the
notes to this release; historical intercepts are downhole lengths from records predating NI 43-101; visually logged intervals are
pending assay and no grade, width or continuity is reported or implied.¹, ², ⁴
Drill-Core Photographs
Massive sulphide of the type intersected at Mary March is dense, uniformly sulphidic rock, dominated
by pyrite and generally grey to brassy in appearance. The copper, zinc, lead, gold and silver values
reported in Table 1, as determined by assays, are carried in chalcopyrite, sphalerite and galena
distributed throughout the sulphide mass. The photographs below are provided to show the character
of the core and are not representative of grade, width, continuity or abundance of mineralization.
Photo 1 – Core box 472.73 to 477.02 m, drill hole MM-26-42, with sample intervals and CuEq grades
Sawn half core from 472.73 to 477.02 m in drill hole MM-26-42. Bars show the Table 2 sample intervals and assay values; depth
markers sit at the sample breaks. Four of the five sampled intervals in this box grade between 2.54% and 4.62% CuEq¹ and lie
within the 9.75 m interval grading 3.3% CuEq¹ reported in Table 1. Selected detail; not representative of interval width, grade,
continuity or abundance of mineralization.
Photo 2 – Massive sulphide, sawn half core, 474.75 to 475.0 m, drill hole MM-26-42
Sawn half core, 474.75 to 475.0 m, drill hole MM-26-42, within the 474.0 to 475.0 m sample (0.98% copper, 4.40% zinc; 3.51%
CuEq¹). Pale, resinous bands, identified during logging as sphalerite-rich, cut across pyrite-dominant massive sulphide carrying
fine brassy sulphide grains; in this sample, zinc is the largest contributor to the CuEq grade. Selected detail; not representative of
interval width or grade.
Photo 3 – Massive sulphide, sawn half core, 479.9 to 480.18 m, drill hole MM-26-42
Sawn half core, 479.9 to 480.18 m, drill hole MM-26-42, within the 479.0 to 481.0 m sample (1.05% copper, 3.13% zinc; 3.04%
CuEq¹). Dense massive sulphide from edge to edge of the cut face: pyrite-dominant, with disseminated brassy sulphide grains
and a contrasting pale band identified during logging as sphalerite-rich. Grade continues below the core box shown in Photo 1:
this piece sits approximately 2.9 m deeper. Selected detail; not representative of interval width or grade.
Photographs are selected details and are not representative of the grade, width, continuity or abundance of mineralization;
assay results are pending for certain pictured intervals and no grade is reported or implied for them.¹, ²
About Canstar Resources Inc.
Canstar Resources Inc. (TSXV: ROX) is a focused VMS exploration company with a portfolio of projects in
established mining jurisdictions. The Company’s flagship Mary March VMS Project (approximately 148
km²) is located within the Buchans District in Central Newfoundland and is being advanced under an
earn-in joint venture with VMS Mining Corporation. The Buchans mining camp is well-known for
producing some of the highest-grade VMS deposits in North American mining history⁵. The Company’s
Skellefte VMS Project (approximately 68,000 hectares) is located in the northern portion of the Skellefte
VMS belt of Sweden, a well-established VMS district. Canstar also holds the Golden Baie Project in
southern Newfoundland, currently subject to an option agreement with Churchill Resources Inc.
For further information, please contact:
Juan Carlos Giron Jr., President & Chief Executive Officer
Email: [email protected] | Phone: (647) 557-3442 | www.canstarresources.com