List of Figures and Illustrations

List of Tables

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The Project property is comprised of more than 3,000 acres of private surface and mineral rights (the Property). The Project includes the past-producing Richmond Hill mine and the historical mines of the Carbonate District, as well as multiple prospective areas where gold has been drill-intersected.

The Project is in the western portion of Lawrence County, South Dakota (Figure 2-1), approximately 4.5 miles northwest of Lead, South Dakota. The former Richmond Hill mine is approximately 44° 22’ 45” N latitude and 103° 51’ 30” W longitude.

In 2021, Dakota Territory Resources Corp, now DTRC LLC, entered into a three-year option agreement (the Option) with Barrick subsidiaries Homestake Mining Company of California and LAC Minerals (for convenience referred to collectively at times as Barrick) to acquire their interests in the Richmond Hill Project area. In 2022, the Option was amended to extend the Option period until March 7, 2026. The Option was again amended in February 2025, extending the option until December 31, 2028. Most parcels in the Option area include both surface and mineral rights, but in some instances the Option only includes mineral rights, as discussed further in Section 3 of this Report. Under the Option, Dakota Gold is obligated to file a 1% royalty against the Option properties upon exercise of the Option. Certain portions of the Project are subject to additional royalties, as described further in Section 3 of this Report.

The Project is near the northwest end of the Black Hills which is an oval-shaped north-northwest-striking mountain range approximately 45 miles by 90 miles in extent along the western side of South Dakota and extending into Wyoming. The Black Hills is a domal uplift where erosion has exposed a window of Precambrian igneous and metamorphic rocks flanked by a 6,500 to 7,000 ft deep sequence of Paleozoic to Mesozoic-aged sedimentary rocks dipping off in all directions on the margin of the uplift, all subjected to intrusive activity in the Tertiary.

The Project is located on the northwestern portion of the Lead dome, a subsidiary dome north of the main Black Hills uplift. The Lead dome developed in response to a major Tertiary intrusive event that also led to development of the Tertiary-aged gold deposits. These Tertiary intrusive rocks have a wide range of compositions and occur as stocks, sills, dikes, laccoliths, and breccia pipes. The Property forms a circular area approximately 2 miles in diameter.

Two major terranes underlie the claims. Precambrian metamorphic rocks outcrop on the southern portions of the Property and consist of metamorphosed volcanic and sedimentary rocks. The western portion of this terrane contains primarily extrusive metavolcanic rocks that appear to be mostly mafic in composition. The metasedimentary rocks on the eastern side consist of phyllite, iron formations, and quartzites. Overlying the Precambrian rock on the north end of the Property is a nearly complete Paleozoic section, which includes the Cambro-Ordovician Deadwood Formation; Ordovician to Mississippian Englewood and the Whitewood and Winnipeg Formations; Mississippian Pahasapa Limestone; and the Pennsylvanian Minnelusa Formation. Tertiary igneous rocks of varying composition have intruded extensively into both terranes.

Several gold–silver deposits and prospective areas exist within the Project boundary. Within the Precambrian terrane, Tertiary-aged mineralization occurs within breccia pipes and altered Precambrian rocks, with minor mineralization in the Tertiary intrusive rocks. Examples include the Richmond Hill deposit, Twin Tunnels, Turnaround, Richmond Hill North, West Thumb, Huskie West, Cleveland, Calvin P, Cole Creek Heights, and Earle.

Within the Paleozoic terrane, mineralization occurs in the Cambro-Ordovician Deadwood Formation along two primary horizons containing the most consistent mineralization. Examples within the Deadwood Formation are Cole Creek in the upper portion and MW-3 Main, MW-3 East, and Chism Gulch in the lower portion. Localized gold mineralization also occurs in the Pahasapa Limestone but is limited to narrow veins and structures in the old Carbonate Camp area.

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Prior to Dakota Gold’s tenure, the Property was drilled by at least 1,056 rotary, RC, and core holes testing multiple prospective areas within the claim boundary. Several of these holes are excluded from the final database due to missing collar coordinates, downhole surveys, or other issues. Since optioning the Property in 2021 to the effective date of this report, Dakota Gold has included an additional 148 diamond drill holes in this resource estimate, representing 157,504 ft of core drilling. As of the date of this Report, the Project remains open in multiple directions and Dakota Gold continues to conduct exploratory drilling of the Property.

Prior to entering into the Option agreement for the Property, Dakota Gold also flew a high-resolution helicopter-borne magnetic and gamma-ray spectrometric survey over the Homestake District. The survey covered an area of 962.4 km² and included the Project area, with the objective of mapping Precambrian lithologies and structure as well as Tertiary intrusive rocks and associated alteration in outcrop, subsurface, and beneath cover. The results of this survey are not publicly available.

From 1984 to 1994, project drilling was completed by St. Joe, Bond Gold, and Homestake. Current industry QA/QC standards were not part of these programs. However, IMC has compared historical drilling data against more recent data using current QA/QC protocols and found that the two populations of historical and current data are similar with no evident errors or biases.

From 2019 to the present, current industry standards for QA/QC have been followed. It is the opinion of the QP for this section that the Richmond Hill assay database of historical and current data is adequate for the estimation of mineral resources and subsequent mineral reserves.

Historical oxide metallurgical testing was conducted primarily at St. Joe’s Technical Center and on-site at the Richmond Hill Metallurgical Testing laboratory. Additional work was conducted at Dawson Metallurgical Laboratories, Bondar-Clegg, Kappes Cassiday & Associates and Heinen Lindstrom and Associates. This data was used to support the design and engineering of the production processing facility at Richmond Hill which operated from 1988 to 1993. Recent metallurgical testing focused on froth flotation of the transition and sulfide material and was completed at BaseMet laboratories in 2024.

The metallurgical test work shows that Richmond Hill oxide material is amenable to cyanide heap processing for the recovery of precious metals. Oxide heap leach recoveries are projected at 89% and 30% for gold and silver respectively. Testing of the transition material indicates it is possible to process low sulfide transition material via heap leaching with gold and silver recoveries of 65% gold and 18% for silver.

Additional metallurgical test work is planned to further define geometallurgical domains, associated metallurgical response, processing requirements and facilitate development of the Richmond Hill process geometallurgical model.

The mineral resource estimate for Richmond Hill includes mineral resources amenable to heap leaching and mineral resources amenable to milling. The mineral resource amenable to heap leaching consists of the oxide and transition material types, and the mineral resource amenable to milling consists of the sulfide material. Table 1-1 presents the mineral resource estimate. The measured and indicated mineral resource amenable to leaching amounts to 269.8 million tons at 0.0135 oz/t gold and 0.141 oz/t silver for 3.65 million ounces of contained gold and 38.1 million ounces of contained silver. Inferred mineral resource amenable to leaching is an additional 254.2 million tons at 0.0103 oz/t gold and 0.090 oz/t silver for 2.61 million ounces of contained gold and 22.8 million ounces of contained silver.

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The measured and indicated mineral resource amenable to milling amounts to 69.6 million tons at 0.0141 oz/t gold and 0.139 oz/t silver for 982,100 ounces of contained gold and 9.68 million ounces of contained silver. Inferred mineral resource amenable to milling is an additional 202.2 million tons at 0.0121 oz/t gold and 0.145 oz/t silver for 2.45 million ounces of contained gold and 29.3 million ounces of contained silver.

The measured and indicated mineral resource for leach and mill material amounts to 339.4 million tons at 0.0137 oz/t gold and 0.141 oz/t silver for 4.64 million ounces of contained gold and 47.8 million ounces of contained silver. Inferred mineral resource for leach and mill material is an additional 456.4 million tons at 0.0111 oz/t gold and 0.114 oz/t silver for 5.06 million ounces of contained gold and 52.1 million ounces of contained silver.

Table 1-1: Mineral Resource Estimate

Notes:

1. The Mineral Resource estimate has an effective date of February 3, 2025.

2. All figures are rounded to reflect the relative accuracy of the estimate and therefore numbers may not appear to add precisely.

3. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.

4. Mineral Resources are based on prices of $2000/oz gold and $25/oz silver.

5. Mineral Resources for leach material are based on a gold equivalent cut-off of 0.0026 oz/t for oxide material and 0.0041 oz/t for transition material. Mineral Resources for mill material are based on a gold equivalent cut-off of 0.0050 oz/t.

6. The gold equivalent value for each material is as follows:

Oxide (Leach): Gold equivalent (oz/t) = gold (oz/t) + 0.00418 x silver (oz/t), based on gold recovery of 89% and silver recovery of 30%.

Transition (Leach): Gold equivalent = gold (oz/t) + 0.00382 x silver (oz/t), based on gold recovery of 65% and silver recovery of 20%.

Sulfide (Mill): Gold equivalent = gold (oz/t) + 0.0127 x silver (oz/t), based on gold recovery of 85% and silver recovery of 85%.

7. The gold equivalent values account for metal recoveries, treatment charges, refining costs, and refinery payable percentages.

8. Table 11-4 accompanies this Mineral Resource statement and shows all relevant parameters for mineral resources.

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9. Includes a preliminary estimated royalty rate of 3.8% averaged across the Project property. The QP has determined that the resource is not sensitive to nominal changes in the royalty rate but has recommended that this estimate be updated for the Project economic and cash flow analysis.

10. Mineral Resources are reported in relation to a conceptual constraining pit shell to demonstrate reasonable prospects for economic extraction, as required by the definition of Mineral Resource in S-K 1300; mineralization lying outside of the pit shell is excluded from the Mineral Resource.

11. The Mineral Resource estimate is also constrained by the Richmond Hill Project Boundary. Only mineralization inside this boundary is included in the Mineral Resource Estimate, though waste removal outside the boundary is allowed.

12. The Mineral Resources reported are contained on mineral titles owned or controlled by Dakota Gold.

13. The Mineral Resources are reported in-situ without any dilution or loss considerations, as a point of reference.

Table 1-2 presents a reconciliation of the January 2025 mineral resource estimate with the S-K 1300 Initial Assessment published in April 2024 (analysis dated current as of October 5, 2023) estimate for mineral resources amenable to leaching. This includes the oxide and transition material. Notable changes include conversion of hard grade estimation boundaries to soft boundaries based on additional data and analysis and updated domains for oxide, transition, and sulfide materials. Updates to cut off grade, recovery rates, costs, gold price, and addition of silver also positively impacted the model.

Table 1-2: Summary of Reconciliation Analysis for Contained Gold Ounces

Note 1: Only gold used to develop resource shell.

Note 2: Silver economics allowed to contribute to resource shell 

The Initial Assessment (IA) presented in this report considers open-pit mining of the Richmond Hill gold deposit in the Black Hills region of South Dakota. Mining will utilize a 29 cubic yard hydraulic shovel with support of a 30 cubic yard front end loader, which will load 150-ton haul trucks. Haul trucks will transport both ore and waste material to designated locations, including waste rock storage facilities (WRSFs) and process facilities. Waste rock will be deposited in a WRSF located north of the pit or used for progressive backfilling of mined out phases to reduce the disturbance footprint and haul distances. Additionally, spent leach material will be moved from the leach pads to the pits as backfill.

Mine planning and design were completed using Geovia Whittle™ (Lerchs-Grossman algorithm) and Surpac™ (version 2024) software. Pit optimization was conducted at a base case metal price of $2,200/oz Au and $25/oz Ag, with designs developed for six mining phases. Production scheduling was completed using MineSched™ software, targeting 10.95 million tons per year of ore delivered to the heap leach facility. Backfilling of pits with leached ore and waste material will commence after completion of Phase 1 and continue through the mine life, with additional regrading and closure activities extending through Year 31.

Open-pit slope designs incorporate 40 ft high benches with 20 ft catch benches, achieving inter-ramp slope angles between 46 and 49 degrees depending on lithology. Haul roads have been designed for two-way traffic using 150-ton haul trucks and include 103 ft road widths and 5.5 ft high safety berms. Roads external to the pit are designed to 120 ft to accommodate dual berms.

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Mining operations will be performed using an owner-operated fleet of primarily leased equipment. Peak production will require up to 16 haul trucks, two blasthole drills, two water trucks, two 600 hp dozers, and a suite of support and maintenance equipment. Up to 186 personnel will be employed during peak operations, including mine operations, maintenance, engineering, and technical support staff, working 24/7 in rotating shifts.

The IA assumes owner-operated mining, and equipment productivity factors, performance curves, and first principles calculations were used to derive required equipment hours, from which operating costs were derived. Operating costs and reflect leased equipment with associated maintenance and labor costs. Mining costs are based on a detailed cost model incorporating consumables, labor, fuel, and maintenance.

Dewatering of the pits will focus on managing meteoric water only, as groundwater inflows will be intercepted and removed through perimeter wells prior to mining. Sumps will be in low points of the pit and surface water management infrastructure will direct contact water to the onsite water treatment plant (WTP).

Cutoff grades for material routing considered the internal cutoff grade. While the economic internal break-even cutoff grade of 0.003 oz/ton of equivalent gold was developed using economic and recovery parameters, 0.005 oz/ton of equivalent gold was applied to prioritize higher-grade material and enhance project economics. Gold equivalent grades were calculated considering both gold and silver values using recovery and metal price assumptions.

In the 1980s and 1990s, considerable environmental baseline information was collected to support historical mine permitting and to support reclamation and closure activities. This information, along with new and additional or updated data, will be required to support future mine development and permitting efforts.

Dakota Gold collects select environmental baseline information required to support planned exploration permitting and assist with reclamation of disturbed sites. Key environmental baseline disciplines required to support exploration drilling permitting include: vegetation, wildlife, cultural, archaeology, and historical. Dakota Gold will also be negotiating additional baseline requirements with South Dakota Department of Agriculture and Natural Resources (SDDANR) as part of its permitting process for a new mine at Richmond Hill.

As part of LAC’s closure program at Richmond Hill Mine, all material classified as acid generating was removed from the Spruce Gulch waste dump and placed in truck compacted lifts back into the historical Richmond Hill mining area. Following placement of that material, the material was capped with clay to minimize oxygen and water infiltration into the compacted potentially acid-generating material. LAC also used this method to remediate the ore material on the heap leach pads, isolating the pads with a similar clay cap. The leach pad and backfilled historical Richmond Hill mining area impoundment covers have met or exceeded original design specifications for limiting infiltration. 

Any potentially impacted groundwater from the former process area, pit impoundment, or Spruce Gulch waste dump facility is actively managed by two on-site water management and treatment systems that have continued to operate throughout the post-closure period. Continued water treatment at these sites would be the responsibility of Dakota Gold once the Option is exercised. The associated costs are subject to post-closure bonding, the obligation for which would be assumed by Dakota Gold upon exercise of the Option.

Capital costs were developed for the mine by RESPEC, for the heap leach facility by Welsh Hagan, and for the process plant by M3. Table 1-3 shows the estimated capital costs for the project under the Measured & Indicated (M&I) case. This includes $384 million in Year -1 and $220 million for sustaining capital. Total capital costs are estimated at $604 million.

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