RC drilling at PolarX’s based gold-silver project in Nevada, USA has defined structural targets for high-grade gold within a bulk tonnage mineralised system environment. Exploration revealed extensive low-grade gold mineralisation associated with weak sulphides at the company’s Star Canyon prospect.
The explorer has identified a concealed fault offsetting the bonanza gold vein target. The regionally important Rochester rhyolite rock unit continued to return wide low-grade gold intercepts and a bulk tonnage heap leach gold-silver target.
PolarX says that bonanza gold and silver veins remain a high-priority target within the extensive low-grade host rock. The targeted bonanza-grade veins are believed to lie above the fault hanging wall and all recent holes were drilled below the footwall of the fault. Previous drilling above the hanging wall of the fault returned up to 9.1m grading 124.4 g/t gold and 48.6 g/t silver. The bonanza grades are likely to be important to overall grade in any possible large bulk low-grade heap leach project and will be targeted along strike in future drilling.
The company is planning induced polarisation and airborne magnetic surveys to be undertaken across the Black-Star Canyon and Fourth of July projects to generate bulk tonnage targets in the Rochester rhyolite. The mineralised Rochester rhyolite outcrops at surface in PolarX’s tenements. The geophysics work aims to locate zones with higher sulphide content and associated increases in gold and silver grade over the current frequent wide intercepts grading up to 0.4 g/t gold from 0.1 in weak sulphide mineralised zones.
The best results from the 11-hole RC program that was drilled in December 2022 include 53m at 0.21g/t gold and 26m going 21 g/t gold. The ground’s low-grade mineralisation is hosted in a similar setting to the nearby large low-grade Rochester gold-silver mine and Spring Valley project. Previous drilling tested the southern part of Star Canyon and future exploration will test for northern extensions and hanging wall bonanza vein targets.
PolarX believes the Humboldt Range project geology is bonanza-style epithermal gold-silver mineralisation and bulk mineable epithermal gold-silver mineralisation similar to many other deposits in Nevada including the nearby large heap leach operations at Florida Canyon and Rochester. The ground was mined between 1865 and 1927 when the old miners chased narrow high-grade gold veins.
PolarX’s Humboldt Range project lies between two large operating heap leach gold-silver mines, Florida Canyon and Rochester. The company’s Black-Star Canyon claims are only 3km from the Florida Canyon mine. Florida Canyon is a 5-million-ounce hydrothermal stockwork-stringer gold deposit with production from 1986 to present. In 1994 heap leach production was 6.53 million tonnes going 0.68 g/t gold with current resources of 72 million tonnes running 0.42 g/t.
The Rochester mine, just 15km from PolarX’s ground is another large heap leach gold-silver producer currently finalising a US$670 million expansion. Pre-expansion production for the third quarter of 2022 was 3.55 million tonnes of ore yielding 8761 ounces of gold and 745,000 ounces of silver with annual production forecast at 35-43,000 ounces of gold and 3-4 million ounces of silver. Rochester has resources of 400 million ounces of silver and 3 million ounces of gold. Spring Valley is only 9km from the PolarX ground and has a resource of 4.1 million ounces of gold.
With large-scale gold-silver heap leach operations surrounding the PolarX ground and the company’s drill results showing a similar style of mineralisation things are building nicely towards a possible resource. All eyes will now be on the geophysics results and possible zones of higher sulphide richer gold-silver mineralisation.
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