Osena Project

Overview

SPMC’s Flagship Exploration Asset

The Osena Project is SPMC’s flagship exploration asset. Located in PNG’s Eastern Highlands, the property covers a significant 738 km² land position within the Kainantu Transfer Zone (KTZ). The property is located southwest adjacent to the Au-Cu producing K92 Mining’s Kainantu Gold Mine.

Priority targets within the Osena project area are Ontenu NE and Ontenu Central, with additional targets identified along structurally prospective corridors of the KTZ, a mineralised trend of more than 45 km that extends across SPMC’s Anga and Osena projects, with K92’s Kainantu Gold Mine in between. The Ontenu prospect complex alone encompasses 5 km x 3 km and includes multiple distinct prospect areas: Ontenu Central, Ontenu NE, Ontenu North (N), Ontenu NW, and Ontenu West.

Drilling at Ontenu NE has returned wide anomalous haloes and high-grade intersections, including 5 m @ 12.84 g/t AuEq* (including 2 m @ 28.06 g/t AuEq) in discovery hole ONED26-009 at Megabe, where step-out drilling has confirmed more than 300 m of mineralised strike, open along strike and at depth.

Project: OSENA – Gold & Copper
Land Package: 738 Km² in the Eastern Highlands District, PNG
Proximity: SW border of K92 Mining in the Kainantu Transfer Zone
Stage: Exploration – Active Drilling in progress | 2 Rigs Deployed

Highlights

Key Project Highlights

01

Strategic Location

A 738 km² package adjacent to (southwest of) K92’s producing Kainantu Gold Mine, sitting on the Kainantu Transfer Zone, the major NE structural corridor that controls high-grade Au-Cu mineralisation across the district.

02

Rich Geological Corridor

Osena hosts multiple epithermal, breccia and skarn occurrences, representing a full range of Au-Cu deposit styles within a single land package. It lies on the Kainantu Transfer Zone, a 45+ km mineralised trend that extends across SPMC’s Anga and Osena projects, with K92’s Kainantu Gold Mine in between.

03

Focus Prospects and Potential

Exploration is concentrated on Ontenu NE and Ontenu Central (active drilling), with a deep pipeline of additional targets across the package still to be advanced to drill-ready status.

Investment case

Key Investment Highlights

01
5m @ 12.84 g/t AuEq* from 160 m in discovery hole ONED26-009 at Megabe (including 2 m @ 28.06 g/t AuEq), and 12.2 m @ 6.24 g/t AuEq (including 2 m @ 16.65 g/t AuEq); step-out drilling has since confirmed more than 300 m of mineralised strike, open along strike and at depth. This builds on maiden drilling at Onki and Jorkol, which returned 92 m @ 0.34 g/t Au from 67 m.
02
A K92-style system on SPMC ground: drilling at Onki, Jorkol and Megabe confirms an intermediate-sulphidation epithermal system at Ontenu NE bearing the hallmarks of K92’s Kora/Judd veins on adjacent ground.
03
Productive core preserved at depth: an intact hydrothermal system; silica cap and phreatic breccia indicate the high-grade core is preserved below the level currently being drilled.
04
District-scale surface endowment at Ontenu NE: strong Au-Cu-Te-As pathfinders across multiple corridors (200 m to >1 km strike), with individual rock chips up to 21% Cu | 13.9 g/t Au | 645 g/t Ag.
05
Large shallow porphyry target at Ontenu Central: a 2 km zoned alteration footprint over a shallow porphyry Cu-Au target beneath confirmed surface gold-copper epithermal anomalies. Individual rock chips up to 73 g/t Au & 3.17% Cu.
06
Fertile across the board: geochemistry confirms an Au-fertile, Cu-porphyry-prospective magmatic system across all prospects.
07
Early-stage, district-scale upside: mineralised occurrences along the Kainantu Transfer Zone, a 45+ km trend extending across SPMC’s Anga and Osena projects with K92’s mine in between; the bulk of the system remains untested.
08
De-risked logistics: road-accessible flagship prospects (Ontenu NE and Ontenu Central) near the town of Kainantu, close to the Ramu Valley grid and only ~160 km by road to the Port of Lae.

Drilling now

The Ontenu Prospect Complex

Ontenu is the most advanced target at the Osena project: a 5 km × 3 km cluster of porphyry Cu-Au, epithermal Au-Cu vein, and Au-skarn occurrences. At surface the project hosts two related but distinct styles of mineralisation: a proximal porphyry Cu-Au system centred on Ontenu Central and West, and a structurally controlled epithermal Au-Cu vein system at Ontenu NE, the focus of drilling to date. Porphyry targets have been modelled at depth beneath Ontenu Central.

These holes are only the start. Only small portions of three of the eight identified NW-trending structures at Ontenu (Jorkol, Onki and Megabe) have been drill-tested, and the silica cap, breccia textures, and multi-element geochemistry all point to higher-grade mineralisation at depth and along strike. Both rigs have moved to Ontenu Central, a 2 km zoned alteration footprint and a large porphyry Cu-Au target at depth, with the next holes at Megabe planned to test for high-grade below and down-plunge of ONED26-009.

Ontenu NE Prospect Overview

SPMC’s maiden drill program at Ontenu NE returned 92 m of mineralisation in May 2026, with gold intersected in five of seven holes and peak re-assay values of 9.92 g/t Au and 2.35% Cu. Drilling then turned to Megabe, a new target in the corridor between Jorkol and Onki: discovery hole ONED26-009 intersected 5 m at 12.84 g/t AuEq* (including 2 m at 28.06 g/t AuEq) and 12.2 m at 6.24 g/t AuEq (including 2 m at 16.65 g/t AuEq), and step-out drilling has since traced the Megabe structures over more than 300 metres of confirmed strike, open along strike and at depth. The results confirm a live, vertically zoned hydrothermal system directly comparable to the Kora and Judd vein deposits that anchor K92’s production next door.

Ontenu NE Overview

A prospective intermediate- to high-sulphidation epithermal system, and the current focus of SPMC’s diamond drilling.

Ontenu NE was identified in 2025 as a set of northwest-trending mineralised structures interpreted as the surface expression of deeper epithermal Au-Cu veins analogous to K92’s Kora and Judd deposits. Surface sampling defined two priority drill corridors:

Onki Fault Area (2025 surface results) multiple high-grade structures returning rock chip samples of:

8.6 g/t Au (0.2% Cu, 32 g/t Ag) in a shear zone
21.2% Cu (214 g/t Ag, 0.41 g/t Au) in a massive-sulphide splay
310 g/t Ag (18.1% Cu, 0.32 g/t Au) (News release: November 11, 2025)

Jorkol Fault Area (southern area of Ontenu NE, 2025 discovery) a new outcrop along strike of a >600 m Au-As soil anomaly. Six 1 m rock-chip samples returned:

3.95 g/t Au, 1.2% Cu, 603 ppm Ag (peak)
2.65 g/t Au, 0.6% Cu, 337 ppm Ag (field repeat, same location as above)
2.18 g/t Au, 0.1% Cu, 100 ppm Ag

Gold across all six samples ranged from 1.14 - 3.95 g/t Au

(News release: September 17, 2025)

Megabe (central area of Ontenu NE, 2026 discovery) the new target in the corridor between Jorkol and Onki, transected by Otitapa Creek, a notable source of alluvial gold mined by local artisanal miners. Mineralisation is hosted in NW-SE-striking fault breccia within metasediments, a comparable geological host and orientation to K92 Mining’s nearby Kora-Judd operations.

(News release: June 16, 2026)

Megabe is one of eight identified mineralised structures at Ontenu, most of which remain undrilled. Only small portions of three of the eight NW-trending structures (Jorkol, Onki and Megabe) have been drill-tested across the five-kilometre Ontenu trend.

(News release: August 24, 2026)

Ontenu NE Drill Results

Active Drilling, Live Results

Megabe (June to August 2026)

Every reported hole targeting Megabe has intersected mineralised structures. Step-out drilling has traced continuous mineralised structures over more than 300 metres of confirmed strike, from ONED26-014 in the northwest to ONED26-012 in the southeast, and the structures remain open along strike in both directions and at depth.

ONED26-009 discovery hole, three mineralised zones:

5 m @ 12.84 g/t AuEq from 160 m, including 2 m @ 28.06 g/t AuEq (27.45 g/t Au, 0.21% Cu, 27 g/t Ag), within 8 m @ 9.28 g/t AuEq from 157 m (Zone 1)
2 m @ 4.13 g/t AuEq (3.26 g/t Au, 0.21% Cu, 45 g/t Ag) from 210 m (Zone 2)
12.2 m @ 6.24 g/t AuEq (4.93 g/t Au, 0.50% Cu, 55 g/t Ag) from 324 m, including 2 m @ 16.65 g/t AuEq (Zone 3, the main Megabe structure)

Zones 1 and 2 are interpreted as the along-strike continuation of the hanging-wall mineralisation intersected in ONED26-007; ONED26-009 intersected this mineralisation about 75 m along strike to the southeast of the ONED26-007 intersection.

(News release: July 6, 2026)

ONED26-007 first hole into Megabe:

12 m @ 3.1 g/t Au and 15.4 g/t Ag from 185 m, including 1 m @ 18.1 g/t Au and 84 g/t Ag

(News release: June 16, 2026)

ONED26-010 to ONED26-014 step-out program, all five holes intersecting mineralised structures:

5.1 m @ 1.79 g/t AuEq from 313.3 m (ONED26-011), including 3 m @ 2.66 g/t AuEq, in a potential fourth mineralised zone at Megabe
18 m @ 0.25 g/t AuEq from 213 m (ONED26-010), a separate set of structures southwest of Megabe, confirming that mineralised structures extend beyond the Megabe corridor

The step-out holes cut the Megabe structures in the upper part of the system, above the interpreted high-grade target zone. The next holes at Megabe are planned to test for further high-grade targets below and down-plunge to the southeast of the high-grade intercepts in ONED26-009.

(News release: August 24, 2026)

*AuEq is based on 100% equal co-recoveries of Au, Ag and Cu using an Au price of US$4,180 per ounce, an Ag price of US$62 per ounce and a Cu price of US$6.20 per lb. All intervals are reported as downhole lengths; true widths have not yet been determined pending further structural interpretation. For ONED26-007, true width is estimated at approximately 30% of the downhole interval, preliminary and subject to confirmation by further drilling.

Onki and Jorkol (May 2026)

May 20, 2026: assay highlights. Gold mineralisation in 5 of 7 holes across two zones.

Onki Fault Area key intercepts:

92 m @ 0.34 g/t Au from 67 m (ONED26-006), including 2 m @ 5.74 g/t Au, 1.49% Cu, 35 g/t Ag from 119 m | peak re-assay 9.92 g/t Au, 2.35% Cu
99 m @ 0.23 g/t Au from 1 m, including 11 m @ 0.18 g/t Au, 0.22% Cu, 1.1 g/t Ag
20.7 m @ 0.21 g/t Au, 0.1% Cu, 2.9 g/t Ag from 42.3 m

Jorkol Fault Area (Southern Area of Ontenu NE) key intercepts:

4.5 m @ 0.77 g/t Au, 0.14% Cu, 19 g/t Ag from 203.5 m, including 0.5 m @ 3.16 g/t Au, 0.62% Cu, 96 g/t Ag with 602 ppm Bi
15 m @ 0.19 g/t Au, 2.4 g/t Ag from 215 m
5.5 m @ 0.36 g/t Au, 7.6 g/t Ag from 117.5 m
8 m @ 0.74 g/t Au, 8.5 g/t Ag from 51 m
3 m @ 1.03 g/t Au, 68 g/t Ag from 43 m

Both high-grade zones are wrapped in wide low-grade halos with pathfinder signatures (As, Sb, Bi, Te) characteristic of intermediate- to high-sulphidation epithermal systems; the same model that supports K92’s Kora and Judd deposits.

Multiple NW-trending structures at Onki remain undrilled. Drilling has since moved to the Megabe target, where hole ONED26-009 returned the discovery intercepts reported above.

(News release: May 20, 2026)

Map view of Megabe drilling, Ontenu NE — Map view of Megabe drilling, showing holes ONED26-007 and ONED26-009 to ONED26-014, mineralised Zones 1 to 4 and structural trends open to the northwest and southeast.

ONED26-009 cross-section at Megabe, Ontenu NE — ONED26-009 cross-section (looking northwest) at Megabe, showing the three mineralised zones intersected in the hole.

Map view of the broader Ontenu prospective area (August 24, 2026), showing the Jorkol, Megabe and Onki drill areas at Ontenu NE, planned holes ONED26-015 and ONED26-016, and holes OCED26-001 to OCED26-004 at Ontenu Central (assays pending).

Ontenu NE Drill Results — Figure 2: ONED26-006 cross-section (SW–NE) at the Onki Zone, showing the silica cap / phreatic breccia interpretation overlying the 92 m @ 0.34 g/t Au intercept and the 2 m @ 5.74 g/t Au (peak 9.92 g/t Au) breccia at 119 m.

Ontenu NE Drill Results Cross Section — Figure 3: ONED25-001 cross-section (SW–NE) at the Jorkol Zone, showing the hole intersecting the Jorkol and Agau vein structures, with the 4.5 m @ 0.77 g/t Au intercept (peak 3.16 g/t Au, 0.62% Cu, 96 g/t Ag over 0.5 m) at 203.5 m and the 5.5 m @ 0.36 g/t Au intercept at 117.5 m. Multiple narrow vein structures remain untested at depth.

Exploration

Exploration Work Summary

SPMC Exploration Work Summary (2024-2026)

Since acquiring the project, SPMC has significantly advanced exploration through systematic field programs:

Comprehensive soil and rock chip sampling programs across Ontenu Central and NE
Structural mapping programs at Ontenu NE, identifying NW-trending mineralised structures, mapped at surface over several hundred metres with geochemical signatures suggesting potential strike extensions beyond 1 km.
Mobilisation of the first-ever diamond drill program at Ontenu NE in late October 2025, with a second rig added in February 2026. Drilling has tested the Onki and Jorkol zones (initial assay results announced May 20, 2026) and the new Megabe target, where step-out drilling has traced mineralised structures over more than 300 m of strike (latest assay results announced August 24, 2026).
First drilling at Ontenu Central in 2026, testing newly mapped NW-SE mineralised trends with four planned holes (OCED26-001 to OCED26-004), assays pending.
Detailed geological mapping at Ontenu Central in early 2026 - a 2 km zoned alteration footprint with a classic porphyry signature and defining the shallow (~400 m) porphyry target beneath surface Au-Cu anomalies.

Historical Work and Data Compilation

Exploration at Osena has been intermittent since the 1980s, with a significant body of historical work including drilling, rock chip sampling, soil surveys, stream sediment sampling, and geophysical data accumulated over multiple exploration campaigns.

Key historical data includes

1,055 line-km of airborne EM and magnetics (Expert Geophysics, 2022), covering 186 km² at 200 m line spacing, as well as a Mobile Magnetotelluric (MMT) survey completed in 2022 that identified numerous high-priority targets. Historical surface sampling has returned grades including up to 73 g/t Au, 960 g/t Ag, 3.17% Cu and 10.6% Zn in rock chips, and a 79 m trench at Ontenu Central assayed 0.75 g/t Au, including 4 m at 4.52 g/t Au.
Over 10,000 historical surface samples including rock chip, soil, stream sediment, channel and pan concentrate samples with assays for Au and a suite of pathfinder elements.
Historical drilling data, including Barrick-era drill holes at Ontenu Central, providing critical observations
Mobile Magnetotelluric (MMT) survey (2022), which identified numerous high-priority targets across the Ontenu area and the Anga project, including a chargeability feature at Anga interpreted as a Kora-Judd look-alike.

Geology

Geological Overview

The Epithermal System With Porphyry at depth

The mineralisation model at Osena is best understood as an epithermal Au-Cu system, driven by a porphyry Cu-Au system at depth. These are analogous to the deposits of the Wafi-Golpu in PNG, Gosowong in Indonesia, and K92’s Kora-Judd system. This mineral system style is characterised by:

A causative dioritic to granodioritic porphyry intrusion emplaced at shallow crustal depths, responsible for generating copper-gold mineralisation in stockwork vein networks and breccia pipes.
Structurally controlled epithermal systems that form in fault, vein and breccia segments around the porphyry margin, carrying bonanza-grade gold, copper and silver mineralisation in quartz-sulphide veins hosted in metasedimentary and intrusive rocks.

At Ontenu, all three components of this system appear to be represented. Advanced argillic alteration in narrow zones, surrounded by phyllic alteration dominates the Ontenu Central and NE areas. Drilling has encountered phreatic breccias and silicified zones consistent with lithocap formation.

Surface rock chips and trench samples reveal the characteristic pathfinder geochemistry (Te, Bi, As, Sb, Mo) of a porphyry-epithermal transition zone.

Regional setting

Regional & Geological Context

The Papua New Guinean Thrust Belt (PNGTB)

The Osena and Anga projects are situated within the Papua New Guinean Thrust Belt (PNGTB), a world-class metallogenic province that hosts some of the largest gold-copper deposits in the Asia-Pacific region and the world. The PNGTB sits above thickened continental crust, formed by the accretion of arc terranes and major mountain building linked to the northward movement of the Australian plate and the southward propagation of a foreland fold and thrust belt.

The Kainantu Transfer Zone (KTZ) SPMC’s Home Corridor

The single most important geological feature for understanding SPMC’s value proposition is the Kainantu Transfer Zone. This major arc-transverse structural corridor sits at the intersection of NW-SE arc-parallel first-order strike-slip fault systems and NNE-SSW transfer structures. This tectonic geometry focuses magmatic-hydrothermal fluid flow and produces the metal-rich, high-grade veins and porphyry systems found throughout the belt.

Most Au-Cu deposits in the PNGTB are located along arc-parallel suture zones and strike-slip shears such as the Ramu-Markham Fault Zone. The Kainantu Transfer Zone acts as a plumbing system, creating high-permeability extensional zones that channeled metal-bearing hydrothermal fluids from depth to the site of ore deposition. SPMC’s Osena project occupies the southwestern segment of this corridor; K92’s Kainantu mine sits in the middle; SPMC’s Anga project holds the northeastern segment.

Deposit Analogy: Why This Setting Matters

The key geological insight from the PNGTB is that Plio-Pleistocene plate reorganisation (roughly 12, 8, 6, and 4-3 million years ago) initiated rapid uplift and crust thinning that allowed gold-enriched magmas to reach shallow crustal levels. Lower water content and shallow depths inhibit premature sulphide saturation, producing highly fertile evolved magmas that deposit their gold and copper in the final stages of crystallisation. Precisely the model for high-grade, smaller-tonnage deposits like those SPMC is targeting.

Au-rich porphyry and epithermal Au formation is optimised under mild transpressional stress, where localised high-permeability extensional zones around fault structures promote focused magma ascent. This produced repeated pulses of major mineralisation across the PNGTB during the Plio-Pleistocene, and SPMC’s prospects sit on structures that experienced exactly these conditions.

SPMC’s Flagship Exploration Asset