InvestorsIssue 03 | Oct 15, 2026
CONFIRMING THE MINERALIZED FOOTPRINT AT YARUMALITO
2026 drilling program advances understanding of the gold-copper system
Yarumalito is one of three 100%-owned resource-stage gold-copper projects in the Mid Cauca belt of central Colombia, south of Medellín. Initial assays from the 2026 drilling campaign confirm wide, continuous intervals of gold-copper porphyry mineralization starting from surface.
When evaluating porphyry systems, key factors include the continuity and scale of mineralization. Our first reported diamond drill hole from the 2026 program at Yarumalito – hole YAR-45 – intersected 399.9 metres of continuous gold-copper mineralization from surface to the end of the hole.
Importantly, this intercept supports our 3D geological model of the core P-1 intrusive suite, which hosts disseminated and vein stockwork mineralization that remains open along strike and at depth.
Figure 1 Left: YAR-45 drill core from interval 189.0 to 190.5 m depth, grading 1.59 g/t Au, 0.19% Cu & 3.6 g/t Ag. Right: YAR-45 drill core from interval 184.9 to 185.6 m depth, grading 1.07 g/t Au, 0.20% Cu & 8.8 g/t Ag.
KEY YAR-45 INTERCEPTS1,2,3
We designed drill hole YAR-45 to test both the vertical and lateral continuity of the P-1 intrusive phase. Highlights include intercepting continuous mineralization from surface to the end of the hole, returning 399.9 metres (m) at 0.45 grams per tonne (g/t) gold equivalent (AuEq) (0.34 g/t Au, 0.09% Cu, 1.21 g/t Ag) from surface to 399.9 m depth, including:
- 33.2 m at 0.81 g/t AuEq (0.68 g/t Au, 0.11% Cu, 1.64 g/t Ag) from 10.3 m;
- 74.7 m at 0.61 g/t AuEq (0.46 g/t Au, 0.13% Cu, 1.41 g/t Ag) from 136.5 m, including 47.0 m at 0.70 g/t AuEq (0.54 g/t Au, 0.14% Cu, 1.72 g/t Ag) from 154.0 m; and
- 36.0 m at 0.65 g/t AuEq (0.50 g/t Au, 0.14% Cu, 1.07 g/t Ag) from 330.0 m.
2026 DRILLING PROGRAM
Our team safely completed a total of four diamond drill holes comprising 1,218 metres on schedule and within budget.
In YAR-45, we intersected predominantly P-1 porphyry or P-1 breccia, along with a complex transitional contact zone with the earlier, weakly mineralized P-0 intrusive phase. The hole remained in continuous alteration and mineralization of variable intensity from surface to the final depth of 399.9 metres, ending in weak alteration and mineralization. See our news release dated October 6, 2026, for further information regarding the drilling program.
We are currently awaiting assays for the remaining three holes: YAR-46, YAR-47 and YAR-48.
Figure 2 Drill rig setup at the Yarumalito Project during the 2026 drilling program.
A LOOK AT YARUMALITO
Yarumalito is located approximately 65 kilometres south of Medellín and 40 kilometres south of the Company’s La Mina project. Gold-copper mineralization is related to Miocene-aged intermediate stocks and intrusive breccias crosscut by late-stage intermediate sulphidation epithermal veins. The Project sits within a major mineralized trend that hosts several significant deposits, including AngloGold Ashanti’s Quebradona project, Aris Mining’s Marmato Mine and Collective Mining’s Guayabales project.
The mineral resource estimate for the project4 is based on 50 historical drill holes completed between 2005 and 2013, comprising approximately 18,000 metres of core. The estimate comprises 66.3 million tonnes grading 0.58 g/t Au and 0.09% Cu, containing approximately 1.23 million ounces of gold and 129 million pounds of copper, reported at a cut-off grade of 0.50 g/t Au.
During our 2024 and 2025 re-logging campaigns, we classified the intrusive complex into three distinct phases: P-0, P-1 and P-2. We identified the P-1 intrusive suite – a fine- to medium-grained quartz diorite characterized by pervasive potassic alteration and well-developed quartz+pyrite±chalcopyrite stockwork veins – as the principal host of the porphyry-style gold-copper mineralization. Late-stage epithermal veining overprints the system, introducing local high-grade gold-silver veins.
Notes
- Reported intervals are downhole core lengths. True width is estimated to be approximately 50% of downhole interval length based on current geological interpretation of sub-vertical P-1 intrusive phase contact orientations.
- Gold Equivalent (AuEq) is calculated using the formula: AuEq (g/t) = Au (g/t) + [Cu (%) x {Cu Price/Au Price} x 22.0462 x 31.1035] + [Ag (g/t) x {Ag Price/Au Price}]. Assumed metal prices: US$3,550/oz Au, US$5.00/lb Cu and US$50/oz Ag. Metallurgical recoveries are assumed at 100% for the purpose of conceptual equivalence pending definitive metallurgical test work; actual recoveries may be lower.
- Cut-off grade applied for the entire drill hole composite interval (from surface to 399.9 m EOH) is 0.10 g/t AuEq with a maximum internal dilution of 5.0 consecutive metres. The additional composite intercepts are reported above a cut-off grade of 0.30 g/t AuEq with a maximum internal dilution of 3.0 consecutive metres.
- Mineral resources that are not mineral reserves do not have demonstrated economic viability. Inferred Mineral Resources have a high degree of uncertainty as to their existence and as to whether they can be economically or legally mined, and it cannot be assumed that all or any part of an Inferred Mineral Resource will be upgraded to a higher category. See the NI 43-101 technical report titled “Technical Report Yarumalito Gold-Copper Property, Departments of Antioquia and Caldas, Republic of Colombia” with an effective date of April 1, 2020, which is available under the Company's profile at www.sedarplus.ca, for further information regarding the project, including details regarding key assumptions, parameters and methods.
LOOKING AHEAD
With assays from the three remaining drill holes pending, our next step is to integrate the complete results from the 2026 drilling program into updated geological and mineral resource models to further define the scope of the project.
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TECHNICAL DISCLOSURE
Tim Smith, P. Geo., Vice President Exploration of GoldMining, has supervised the preparation of, and verified and approved, all scientific and technical information contained herein. Mr. Smith is also a qualified person as defined in National Instrument 43-101 – Standards of Disclosure for Mineral Projects (“NI 43-101”).
Technical disclosure regarding the projects described herein has been prepared by the Company in accordance with NI 43-101, which establishes standards for all public disclosure an issuer makes of scientific and technical information concerning mineral projects. These standards differ from the requirements of the U.S. Securities and Exchange Commission (the “SEC”), and the scientific and technical information contained herein may not be comparable to similar information disclosed by domestic United States companies subject to the SEC’s reporting and disclosure requirements.
FORWARD-LOOKING STATEMENTS
Certain of the information contained in this newsletter constitutes “forward-looking information” and “forward-looking statements” within the meaning of applicable Canadian and U.S. securities laws (“forward-looking statements”), which involve known and unknown risks, uncertainties and other factors that may cause the Company’s actual results, performance and achievements to be materially different from the results, performance or achievements expressed or implied therein. Forward-looking statements, which are all statements other than statements of historical fact, include, but are not limited to, statements respecting the timing and receipt of pending assay results for drill holes YAR-46 to YAR-48, the integration of drilling results into an updated geological model and mineral resource model, the continuity of mineralization, the exploration potential of the Yarumalito Project, the Company’s plans and expectations regarding its projects and future opportunities and proposed work and studies thereon. Forward-looking statements are based on the then-current expectations, beliefs, assumptions, estimates and forecasts about the business and the markets in which GoldMining operates. Investors are cautioned that all forward-looking statements involve risks and uncertainties, including: the inherent risks involved in the exploration and development of mineral properties, the risk that pending assay results may not be consistent with results reported herein, fluctuating metal prices, unanticipated costs and expenses, risks related to government and environmental regulation, social, permitting and licensing matters and uncertainties relating to the availability and costs of financing needed in the future. These risks, as well as others, including those set forth in GoldMining’s Annual Information Form for the year ended November 30, 2025, and other filings with Canadian securities regulators and the SEC, could cause actual results and events to vary significantly. Accordingly, readers should not place undue reliance on forward-looking statements. There can be no assurance that forward-looking statements, or the material factors or assumptions used to develop such forward-looking statements, will prove to be accurate. The Company does not undertake to update any forward-looking statements, except in accordance with applicable securities law.