Dutch Gold Resources said it has discovered a site at Montana in the US with 2.8 million ounces of proved and probable gold reserves, worth nearly $3bn.
Dutch Gold CEO Daniel Hollis said the Basin Gulch project, which is spread across 1,000 acres, has the potential to supply up to 7.5 million ounces of gold.
"It could be in the top 5% - in terms of size - of all gold mines in the US," Hollis said.
The permit application process for the project will commence in the first quarter of this year and will concentrate on a potentially high-grade underground system.
The project is in the late-stage of exploration, which involves identification of gold reserves and preparatory work for mining, and will take one year to develop.
The company said it plans to invest $100m for gold extraction work over a ten- to 15-year period.