i-80 Gold Corp. has announced positive results from its ongoing surface drill program, including step-out drilling at depth, at the company’s Granite Creek property in Humboldt County, Nevada.
High-grade results from the surface drill program, targeting the expansion of mineralization at depth below the mine workings at Granite Creek, suggest significant expansion potential, the company said. To date, fourteen holes have been completed and the assays received for the first four holes show impressive gold grades and widths of mineralization, i-80 Gold added.
“The expansion program at Granite Creek is demonstrating the significant upside opportunity and confirm the potential to materially increase high-grade resources," said Tyler Hill, senior geologist at i-80 in a statement.
“The fault structures are becoming more competent at depth suggesting the potential for increased widths, improved ground conditions and mineability, and enhanced continuity within the gold-bearing structures. Visually, every hole of the step-out program has intersected strong alteration and faulting,” he added.
READ: i-80 Gold sees US$8.2M in 3Q revenue following transformative quarter highlighted by new Nevada mining complex acquisition
Highlight results from initial deep drilling include:
- 12.8 grams per ton gold (g/t Au) over 6.1 m in hole iGS21-01
- 16.3 g/t Au over 7.1 m in hole iGS21-03
- 14.7 g/t Au over 10.2 m and 16.4 g/t Au over 3.4 m in hole iGS21-04
- 16.5 g/t Au over 5.3 m and 5.1 g/t Au over 6.7 m in hole iGS21-05
The step-out program is one of multiple target areas being drilled in the current program, comprising over 20,000 meters from surface and underground. It is expected to continue well into the new year. The primary goal of the 2021 drill program is to advance underground and open pit opportunities to production. An important part of the program is also to expand resources at depth and along strike where the deposit remains open.
“When combined with wide-spaced historic drilling in the down-dip expansion area, drilling has defined high-grade mineralization over a strike length of at least 600 meters and 250 meters of dip length and remains wide open at depth and along strike to the north,” said the company.
“High-grade mineralization at Granite Creek occurs in a near-identical geological setting as that at the multi‑million ounce Turquoise Ridge Mine located immediately to the; proximal to a major regional fault on the eastern edge of the large Osgood Mountains intrusive complex. The Granite Creek deposit remains open at depth and along strike from the existing underground workings,” it added.
Refractory mineralization from the underground operation at Granite Creek is expected to be trucked to Twin Creeks for processing initially, pursuant to the agreement recently entered into with Nevada Gold Mines until i-80’s Lone Tree facility is operational.
A preliminary economic assessment for Granite Creek was released last week based on the current resource. It demonstrated the economic opportunity with a net present value (NPV)at 5% of US$244.9 million and an after-tax internal rate of return (IRR) of 34.2% prior to considering the potential benefits that could come from using the existing processing facilities at Lone Tree or incorporating any of the drilling performed by the company in 2021.
Drilling has been completed at approximately 12,500 meters of the over 20,000-meter ongoing drill program.
“Initial underground rehabilitation to facilitate definition drilling has been completed as part of an aggressive plan to re-commence mining from the existing mine workings and several areas are being prepared for test mining in advance of production ramp-up targeted for H1-2022,” i-80 Gold said.
The company noted that all samples were submitted to Paragon Geochemical Assay Laboratories (PAL) of Sparks, Nevada, which is an ISO 9001 and 17025 certified and accredited laboratory, independent of the company.