PolarX strikes hyper-grade copper at Caribou Dome in Alaska

PolarX (ASX:PXX) drilled nine holes for 2133m at Caribou Dome. Eight hit what the company is calling “hyper-grade” copper.

Best results were 18m at 2.84% copper and 3.65g/t silver from 99.4m in CD25-005, including 8.5m at 5.98% copper and 1.1m at 13.23%.

That same hole also hit 7.9m at 4.48% copper and 5.56g/t silver from 183.8m, with 2.4m at 9.54% copper.

Other strong hits: 11.3m at 3.49% copper from 74.6m in CD25-004, 10.5m at 3.55% from 91.2m in CD25-003, and 5.3m at 6.12% from 239.9m in CD25-009, including 2.5m at 10.82% copper and 17.68g/t silver.

That last hit clocked in 282m below surface and the system is still open underneath.

These new hits are extending copper mineralisation at depth at Snow Gully, a zone which sits at the heart of the Caribou Dome project.

PolarX also found a possible new gold-silver style in hole CD25-006, with 4.3m at 0.34g/t gold and 1.4g/t silver from 106.2m, near some lower-grade copper and semi-massive sulphides.

This could be a low-grade gold zone leading into the hyper-grade massive sulphides, which has been missed before.

Drilling on type section 4 pushed mineralisation deeper and found copper under areas once thought to be just iron-rich sulphides.

On type section 2, three out of four holes hit hyper-grade copper. The one miss was probably due to a small fault offset, less than 10m.

Type section 2 features ore intercepts in holes CD25-003, CD25-004 and CD25001, but not in CD25-002. PolarX geological logging indicates a fault offset in this zone and will therefore drill beneath CD25-002 for down dip continuity in 2026. Pic: PXX

That’s given PolarX the confidence to drill under the offset zone in 2026 and try to reconnect the mineralisation.

PolarX is relogging old core and building a new 3D model to help pick the next drill targets.

They’ve also collected conductivity data, and consultants reckon the massive sulphides stand out from other rocks, so Caribou Dome is a good fit for downhole EM surveys.

All this will feed into a big 2026 drilling campaign of over 10,000m, kicking off in early June after site prep in May. It is funded via a currently approved US$6.9m budget in conjunction with 15% minority JV partner and ASX gold giant Northern Star Resources (ASX:NST).

It’s already a genuinely high-grade copper asset, with a June 2023 resource of 7.2Mt at 3.1% Cu and 6.5g/t Ag.

Those are rare copper numbers by global standards, and these new hits show there’s still room to grow below the current 300m deep envelope and along strike.

Caribou Dome sits next to the Zackly copper-gold-silver deposit. 

Together, Alaska Range has 11.2Mt with 269,000t of copper, 213,000oz of gold and 3.13Moz of silver.

PolarX’s 2024 scoping study for Alaska Range outPolarX’s 2024 scoping study for Alaska Range showed a pre-tax NPV of A$625m and an IRR of 73.9%, using copper at US$8500/t and gold at US$1900/oz. Prices for both commodities have surged to record levels since, with copper paying US$12,313/t and gold futures at US$4833/oz.