All of the below information with respect to the Expanded Silicon Project owned by AngloGold Ashanti North America Inc., an indirect subsidiary of AngloGold Ashanti plc (“AGA”), with the exception of the schematic long section which was produced by Altius based on information disclosed by AGA, has been excerpted or derived from AGA’s technical disclosure, including the Technical Report Summary, Silicon Project, An Initial Assessment Report, effective December 31, 2021 (the “Silicon TRS”), the Technical Report Summary, Merlin deposit, Expanded Silicon Project, An Initial Assessment Report effective December 31, 2023 under AGA’s (the “Merlin TRS”), and the NI 43-101 Technical Report for the Merlin deposit, Expanded Silicon Project, Nevada, USA, effective December 31 2023 (the “Merlin 43-101”). Additional information has been taken from various AGA news releases and presentations as referenced.
Readers should consult the Silicon TRS and the Merlin TRS, available for review under AGA’s profile on EDGAR, and the Merlin 43-101, available for review under AGA’s profile on Sedar.
The information included here is subject to the assumptions, qualifications and procedures set out in the Silicon TRS, Merlin TRS and Merlin 43-101, and is qualified in its entirety with reference to the full text of the Silicon TRS, Merlin TRS and Merlin 43-101, respectively.
The technical information presented herein has been reviewed and verified by Lawrence Winter, Ph.D., P.Geo., Vice President Generative & Technical for Altius, a Qualified Person as defined by National Instrument 43-101 - Standards of Disclosure for Mineral Projects.
Silicon Gold 1.5% NSR Royalty, Nevada
The Silicon Project is located near Beatty in Nye County, southern Nevada. It was originated in 2014 under a generative exploration focused grubstake agreement between Renaissance Exploration (since merged to form Orogen Royalties) and Callinan Royalties (since merged with Altius) that resulted in the creation of a 1.5% NSR royalty.
On February 22, 2022 AGA published an initial 3.37 M ounce maiden inferred mineral resource estimate (120.44 million tonnes at 0.87 g/t gold) for the Silicon (Central) deposit. In February 2024, AGA provided an update for the ‘Expanded Silicon Project’, which includes both the Silicon and Merlin gold deposits, which was highlighted by the announcement of an initial Inferred Mineral Resource of 9.05 million ounces at the Merlin deposit (283.9 Mt at 0.99 g/t). This is in addition to the now updated more than 4 million ounce Mineral Resource estimate (121.56 at 0.87 g/t Indicated Mineral Resource for 3.4 Moz and 36.03 at 0.70 g/t Inferred Mineral Resource for 0.81 Moz) previously published for the adjacent Silicon deposit. It is noted from AGA’s disclosure in the Merlin TRS and Merlin 43-101 that the initial resource estimate for Merlin only includes a portion of the modelled mineralization. While there are three fault bounded mineralized 'estimation domains' (1500, 2500, 3500) modelled, it is stated by AGA that “only estimation domain 3500 had sufficient drill density, grade continuity and geological continuity to be reported as an Inferred Mineral Resource”. The 1500 and 2500 domains provide immediate targets for further drilling and have the potential to be incorporated into the resource estimate once the drilling density is sufficient.
The images below, taken directly from the Merlin 43-101 shows the three estimation domains at Merlin, of which only the 3500 domain makes up the whole of the December 31, 2023 mineral resource estimate of 9.05 million ounces for Merlin.
With an update on February 19, 2025, AGA has added approximately 3 Moz to the Merlin resource for a total Inferred Resource at Merlin of 12.1 Moz gold in oxide (355.11 Mt @ 1.06 g/t gold). Exploration and delineation drilling are ongoing. The table below summarizes the current Mineral Resource estimate for various deposits held by AGA in the Beatty district, including Merlin and Silicon, effective as of Dec 31, 2024.
Notes on Mineral Resource Table:
Rounding of numbers may result in computational discrepancies in the Mineral Resource tabulations. To reflect that figures are not precise calculations and that there is uncertainty in their estimation, AGA reports tonnage, grade and content for gold to two decimals. All ounces are Troy ounces. “Moz” refers to million ounces. The Mineral Resource tonnages and grades are reported in situ and stockpiled material is reported as broken material.
All disclosure of Mineral Resource is exclusive of Mineral Reserve. The Mineral Resource exclusive of Mineral Reserve is defined as the inclusive Mineral Resource less the Mineral Reserve before dilution and other factors are applied.
1Based on US$1,900/oz gold price unless otherwise stated
2Property currently in a development stage
3Property currently in exploration stage
4 The Expanded Silicon project includes the Silicon and Merlin deposits. The Mineral Resource Silicon deposit is based on a gold price of $1,750/oz.
5Property currently in exploration stage
While AGA has not yet released a new footprint of the updated mineral resource estimate at Merlin, they did state in their 2024 Annual Report that “high-grade zones and well-mineralised stratigraphic units were refined and expanded, enhancing the mineralisation model and leading to an increase in the declared Inferred Mineral Resource”.
AGA completed 132 kilometres of drilling at Merlin in 2024 and is currently working on additional infill and expansion drilling, resource upgrades, and engineering studies to support a pre-feasibility study planned to be released in H2 2025. The focus of the ongoing drilling is thought to be largely within the 3500 domain as AGA stated during their FY2024 earnings call presentation that “infill drilling to classify a portion of the deposit from an indicated resource in the 3500 zone has continued to intercept broad zones of between 0.5 and 1.8 grams per tonne mineralized intercepts”.
Background and Summary
In June 2017, Renaissance signed an exploration option agreement with AGA for Silicon following an initial geological mapping and prospecting program that identified an extensive area of alteration deemed highly prospective for epithermal gold mineralization.
In early 2018, AGA proceeded to drill test the target area resulting in the almost immediate discovery of gold mineralization in the Silicon (Central) area. The first hole was lost but the second hole (“SD-0004”) intersected 79m @ 1.76 g/t Au and marked the discovery of the Silicon deposit. The initial resource estimate was announced by AGA in March 2022 and updated in February of 2023. A maiden Merlin resource estimate was released in February, 2024.
AGA went on to meet its exploration spending and option payment commitments to earn a 100% interest in the project, subject to a 1% NSR royalty in favour of Orogen, which is separate from the 1.5% NSR royalty in favour of Altius. Altius is also a major shareholder of Orogen.
In 2024 AGA published a Technical Report Summary as part of its Annual Report (Form 20-F) that provides an initial assessment of the Merlin resource along with a conceptual mining scenario, which suggests a 14-year life of mine with substantial gold production in the early years. A pre-feasibility study ("PFS") for the Expanded Silicon Project is currently in progress.
The basis of the ongoing PFS targets oxide ore only while AGA recently stated there is "significant upside potential from deeper ore horizons and nearby exploration targets" and that infill and extension drilling programs continue.
Recent drill results published by AGA show some of the most significant oxide gold drill results to date at Merlin, including:
- 161.6 metres @ 5.85 g/t gold (MER-23-243-RD)
- 190.4 metres @ 5.12 g/t gold (MER-23-245-RD)
- 144.5 metres @ 10.53 g/t gold (MER-24-0267-RD)
Moreover, AGA also reported in their Q1 2024 Exploration Report a “significant intercept” from a geotechnical hole (ground water testing) drilled 900m north of the resource delineated at the Silicon Deposit.
Subsequently, AGA has reported in its Q4 2024 Exploration Report that “During Q4, 29 km of drilling was completed, continuing the resource definition drilling at Merlin. A deeper drillhole was also completed to the east that tested the hanging wall of the Bare Mountain Fault, with encouraging visual observations and results pending”, which provides some verification of ‘Target 2”. See figure below.
AGA has recently noted that it is evaluating the new discoveries as part of a “Tier 1 production opportunity in Nevada” with the potential to produce >500,000 ounce per year, with the Technical Report Summary filed by AGA stating potential production rates as high as 1 – 1.8 Moz of gold per annum in years 3-4. AGA’s conceptual development plan for the district envisions the North Bullfrog deposit being developed with initial production expected in the next three years, to be followed by Merlin and Silicon.
The following schematic long section through the Silicon and Merlin deposits depicts the extent of the current resources outlined by AGA at Silicon and Merlin as well as the mineralization outlined by AGA in domains 1500 and 2500 adjacent to the current Merlin resource. It also shows exploration targets 1 and 2 as outlined by AGA and the possible extension of mineralization 900m to the NW of the delineated resource at Silicon as referenced by AGA in their Q1 2024 Exploration Report as a “significant intercept” from a geotechnical hole (ground water testing).
Silicon Royalty Agreement