Toronto, Ontario — December 18, 2025 — Leads & Copy — G2 Goldfields Inc. (TSX: GTWO; OTCQX: GUYGF) has announced the findings of its Preliminary Economic Assessment (PEA) for the Oko Gold Project in Guyana, South America.
The PEA outlines a combined open pit and underground operation with a 14-year mine life, based on drilling completed up to August 31, 2025. The project incorporates 1.6 million ounces of gold in the Indicated category and 1.9 million ounces of gold in the Inferred category, with production averaging 281,000 ounces per year from years 2 through 11.
Daniel Noone, CEO of G2, stated that the PEA places the Oko Project among the most attractive development projects globally, with the potential to generate significant annual production at an average AISC cost of $1,137/oz. He added that Guyana actively promotes the development of large-scale gold mining.
Total production over the 14-year mine life is estimated at 3.2 million ounces of gold with an all-in sustaining cost (AISC) of $1,191 per ounce ($1,137 per ounce from years 2-11). The Oko project will use conventional open pit mining and mechanized long hole open stoping underground mining, with on-site treatment of the mined material through a conventional circuit.
The open pit mine is anticipated to have a life of six years, including two years of pre-stripping, while the underground mine is anticipated to have a life of 14 years, including 18 months of development. The PEA is based upon the Company’s updated Mineral Resource Estimate (MRE) with an effective date of November 20, 2025. A technical report will be filed on the Company’s website and under its SEDAR+ profile within 45 days of the news release.
The MRE includes all drilling data obtained up to the end of August 2025, with a total inventory of 666 drill holes across 170,329 meters. The estimate was prepared by Micon International Limited in accordance with National Instrument 43-101 with an effective date of November 20, 2025.
Mining at the Project is planned to integrate both conventional open pit mining methods and mechanized long hole open stoping underground mining. The open pit mine will have a LOM of six years, including 2 years of pre-stripping, while the UG mine will have a LOM of 14 years, including 18 months of development.
The open pit mine is expected to have a production rate that averages 4,500 tpd over a 14-year LOM. The UG operation will take place in three areas: OMZ, Ghanie and the New Oko Discovery and will employ a long hole open stoping mining method via ramps, including transverse stoping and longitudinal stoping variations. The average UG production rate is expected to be 1,900 tpd of mineralized material.
The proposed process plant design for Oko is based on a standard metallurgical flowsheet to treat gold bearing material and produce doré. The process plant is designed to nominally treat 3.6 Mt per year and will consist of comminution, gravity concentration, cyanide leach and adsorption via CIL, carbon elution and gold recovery circuits.
LOM total site costs are estimated at approximately $947 per ounce of gold produced, excluding royalty costs. The PEA incorporates two federal royalties: a 3.0% net smelter return (NSR) royalty for underground production and an 8.0% NSR royalty for open pit production. The LOM AISC is estimated to be $1,191 per ounce of gold produced based on average annual gold production of 228,000 ounces over the 14-year LOM.
Initial capital costs are estimated at $664 million, including contingencies of $108 million (20%) with LOM sustaining costs estimated at $366 million.
With the completion of the PEA, the Company is now able to submit its preliminary mine design to the Environmental Protection Agency (EPA) to apply for the environmental permit for the Oko Project. The permitting process involves obtaining environmental authorization from the EPA following the submission and approval of an Environmental Social Impact Assessment (ESIA), which the Company expects to file in Q1 2026.
During mine construction, the workforce assumed in the PEA is projected to peak at approximately 1,250 personnel over an estimated 18-month period. Once in operation, the mine and processing plant are expected to sustain an average workforce of approximately 800 employees.
Drilling continues to target open extensions of high-grade mineralization found immediately outside mineral resources where assays are pending on drilling with visible gold mineralization confirming the potential to add additional gold ounces.
Richard Gowans, P.Eng is responsible for metallurgy, recovery methods and process plant operating costs. William Lewis, P.Geo. is responsible for property description, geology, drilling, sampling and the mineral resource estimate. Peter Szkilnyk, P.Eng. and Moe Hashmi, P.Eng. are responsible for the mining methods and capital and operating costs related to the open pit and underground mining. Chris Jacobs, C.Eng, MIMMM, MBA is responsible for the economic analysis. William Lewis, P.Geo., is responsible for the environment and permitting aspects. Dan Noone (CEO of G2 Goldfields Inc.) has also reviewed and approved the scientific and technical information in this news release.
Jacqueline Wagenaar, VP Investor Relations, can be reached at +1.416.628.5904 x.1150 or j.wagenaar@g2goldfields.com.
Source: G2 Goldfields Inc.
