VANCOUVER (miningweekly.com) – Vancouver-based explorer Corvus Gold has enlarged the Nevada-based North Bullfrog project's combined compliant measured and indicated resource by 30%, supporting the TSX-listed stock's rise on Tuesday of more than 4% to C$1.23 a share.

Corvus said the updated resource assessment comprised a two-phase approach, with Phase 1 seeing an early-stage, higher-grade mix of mainly oxide mill processing and oxide heap leach processing. Phase 2 includes mainly heap leach ore.

Assuming openpit mining and a gold price of $1 250/oz and $16.50/oz for silver, the National Instrument 43-101-compliant technical report calculated a measured and indicated resource contains 904 000 oz of gold and 5.46-million ounces of silver at an average grade of 0.8 g/t gold and 4.86 g/t silver in 35-million tonnes.

The report also outlined maiden sulphide resources for the project's first stage, holding 89 000 oz of gold and 343 000 oz of silver at a grade of 1.46 g/t gold and 5.64 g/t silver in 1.89-million tonnes using standardised ambient atmospherics oxidation processing in the proposed mill facility.

Corvus said 99% of the proposed mill material is now located in the measured and indicated resources categories.

For the second phase of the project, the mine plan is based on indicated resource estimates of 855 000 oz of gold and 2.57-million ounces of silver grading 0.22 g/t gold and 0.65 g/t silver in 123-million tonnes of material.

"This initial phase has approximately one-million measured and indicated resources gold ounces and over five-million silver ounces which outline potential for a future mining operation that we believe could be complemented by the Mother Lode project, which is located 6 km to the south-east," president and CEO Jeff Pontius stated in a press release.

"Additionally, this study provides a first look at the viability of integrating higher-grade sulphide mineralisation into the mine plan, which potentially opens the door for future resource expansion in this class of mineralisation. We at Corvus look forward to the integration of the Phase 1, North Bullfrog project with the Mother Lode project, which we believe could deliver an exciting new, low cost, Nevada gold mining project," he said.

Corvus controls 100% of its North Bullfrog project, which covers about 72 km² in southern Nevada. The property package is made up of a number of private mineral leases of patented federal mining claims and 865 federal unpatented mining claims.

The project has excellent infrastructure, being adjacent to a major highway and power corridor as well as a large water right. The company also controls 65 federal unpatented mining claims on the 522 ha Mother Lode project, of which it owns 100%.