Infill drilling by Blackrock Silver (TSXV: BRC) at its Tonopah West project in southwest Nevada has expanded and confirmed the continuity of high-grade gold and silver in the one of the shallowest parts of the resource. Its shares rose 8.1%.

Highlight holes include TXC24-087 which cut 2.6 metres grading 1,920.93 grams silver per tonne and 20.26 grams gold, including 1.1 metres at 4,328 grams silver and 46.5 grams gold, the company reported on Tuesday. That hole, drilled from 172.2 metres depth, is part of a 20,000-metre program of drilling across 50 holes that started in July and is aimed at infilling and converting resources. It’s expected to wrap up by the end of the year.

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“(The drill program has) been successful in stepping out beyond the existing resource envelope identifying significant near-surface expansion potential at higher-than-average grades,” Blackrock CEO and president Andrew Pollard said in a release.

“These findings bolster our confidence in the model presented in our recent preliminary economic assessment and suggest the possibility of shortening the pre-production development timeline as we track high-grade gold and silver mineralization closer to the surface.”

The results follow Blackrock’s release six weeks ago of its preliminary economic assessment (PEA) for Tonopah West, which gave it a post-tax net present value (at a 5% discount) of $326 million, with capital costs of $178 million (including a $22 million contingency). The PEA pegged the project’s post-tax internal rate of return at 39.2%, with a 2.3-year payback period. It used a base gold price of $1,900 per oz. and silver price of $23 per ounce.

Company shares traded for C$0.41 apiece on Tuesday morning in Toronto, hitting a new 52-week high and valuing the company at C$107.5 million.

Other highlight holes include TXC24-101, which cut 1.3 metres at 687 grams silver and 6.56 grams gold from 137.6 metres depth; and TXC24-092, which returned 3.3 metres of 470.56 grams silver and 5.35 grams gold, from 141.6 metres depth, including 1.1 metres of 534 grams silver and 6.9 grams gold.

New gold-silver chute
TXC24-087 and TXC24-101 were among five holes that defined a new high-grade gold and silver chute along the Merton/Bermuda high-grade vein system, Blackrock said. The chute is about 175 metres long and is open to the northwest and southeast. Another high-grade chute starts with TXC24-092, suggesting a recurring pattern of high-grade gold and silver along the strike of the vein system.

The company’s drill program aims to upgrade about 1 million inferred tonnes of high-grade silver and gold to measured and indicated resources in the Bermuda and Merten vein systems. Those systems are located in an area where veins are shallowest and go down 200 to 300 metres.

Tonopah West hosts 6.3 million inferred tonnes grading 2.82 grams gold per tonne and 237.8 grams silver, for 577,000 oz. of gold and 48.5 million oz. of silver, according to the PEA.

The project is being developed four years after discovery at the site along US Highway 95 about 350 km northwest of Las Vegas.