Corvus Gold (TSX:KOR,OTCQX:CORVF) released a new preliminary economic assessment (PEA) for its North Bullfrog project in Nevada, and the results appear largely positive. It incorporates all drill results through 2014 from its recently discovered high-grade YellowJacket deposit. Overall, the oxide, drill and blast surface mine will require initial capex of $175 million for an after-tax NPV of $246 million and an IRR of 38 percent with a 2.2-year payback period. Those numbers are for a gold price of $1,200 per ounce, a level that gold has had trouble staying above over the past three months. However, the PEA also includes results for a gold price of $1,000 — in that scenario, the after-tax NPV would shift to $102.9 million, while the IRR would still be sitting at a respectable 20.5 percent with a three-year payback period. Additionally, WhittleTM based the mine pit on a gold price of $900 for the purposes of PEA analysis. "By using a conservative US$900 gold price driven WhittleTM pit to define the PEA base case pit design the project demonstrates potential to perform well in the current gold price environment," said Jeff Pontius, Corvus Gold's CEO, in Tuesday's release. North Bullfrog is expected to have a mine life of 10 years and a very low strip ratio of 0.6 to 1. Operations are expected to produce 149,000 ounces of gold annually for the first six years before dropping to 68,500 ounces per year for the remaining four, all at an average cash cost of $635 per ounce of gold. North Bullfrog will also put out life-of-mine silver production of 2.49 million ounces. "The results from this initial analysis of the North Bullfrog deposits have clearly illustrated the economic potential of this new and emerging Nevada Gold District," said Pontius. "The unique mix of a high-grade vein/stockwork deposit surrounded by oxide heap leach deposit has resulted in a potentially exceptional, low strip, open pit, mining project in one of the best jurisdictions in the world."