Ground Breakers: Northern Star flags major underground resource update at Kalgoorlie's Super Pit

Northern Star posts major resource and reserve update for 2022
Another 1Moz in inferred mineral resources takes its underground resource beneath the Super Pit to 5Moz
1.1Moz at 10.3g/t added at Goodpaster resource near Pogo mill

The Super Pit is a thing of wonder, a pockmark visible from space that is so big it’s been turned into the best tourist attraction in the WA gold town of Kalgoorlie not known as The World’s Tallest Bin.

(Google it, you won’t be disappointed.)

That’s only been the case since 1989 when Alan Bond (the Alan Bond) pieced a bunch of different mines together on the 60Moz Golden Mile and ordered the shotfirers to start blowing the place up.

Until then it was a collection of underground mines featuring more than 3000km of underground workings, stumbled upon from time to time with the detection of voids in the pit wall.

After more than 30 years as part of the Kalgoorlie Consolidated Gold Mines banner, the Golden Mile’s first sole owner Northern Star Resources (ASX:NST) is again firming up plans to take it underground after announcing a 1Moz increase to an inferred mineral resource at the Super Pit known as the Fimiston Underground.

Coming as part of a major resource and reserve upgrade, Australia’s second biggest gold miner says it is the first glimpse of a “new world class system” that could keep the 129-year-old Golden Mile humming for years to come.

Super Pit promises super growth

The Super Pit is the cornerstone of Northern Star’s 1.6Mozpa portfolio across WA and Alaska, which NST plans will eventually recapture some of its old glory and form a 650,000ozpa block of the 2Moz it hopes to produce annually from 2026.

Locals have long mused about the potential the mine, run on a short leash for years by its previous North American owners Newmont and Barrick, would belie its short reported mine life with a long term rebirth as an underground operations.

The Fimiston Underground resource now boasts an impressive 5Moz, firming its long term potential.

It comes within a broader 56.4Moz group resource which has grown by 4.3Moz over the past year, an update that also includes a maiden 1.1Moz resource at an impressive grade of 10.3g/t at the Goodpaster deposit 2km west of the Pogo mill in Alaska.

NST now boasts ore reserves of 20.7Moz, with Pogo growing to 1.8Moz at 8.5g/t and the Kalgoorlie operations to 13.2Moz, including KCGM, Carosue Dam, Kanowna Belle and South Kalgoorlie.

“Our ongoing exploration success highlights the significant opportunity that exists within our Tier-1 asset portfolio to grow the gold resource base, particularly through the extension of known mineralisation at depth at KCGM,” NST boss Stuart Tonkin said.

“We continue to focus our exploration efforts on extending mine lives and developing our three production centres.”

On the down side for Northern Star, it suffered a fall in resources at its Yandal operations in WA with reductions at its Jundee mine, but has 170,000 assays waiting to be returned which aren’t included in its resource model.

It also saw reductions of 2.4Moz of resources and 600,000oz of reserves from its sale of the Kundana mines to Evolution Mining (ASX:EVN) last year.

RBC mining analyst Alex Barkley said the result would boost confidence, particularly in Northern Star’s struggling Pogo mine.

“A positive Reserve and Resource update for NST,” he said in a note to clients.

“Excluding divestment and projects, NST’s gold Reserves increased 1% and Resources were up 4%.

“The result continues NST’s long track record of organic gold discovery, with the two shortest-life sites the main beneficiaries in this year’s annual update.

“Important upgrades were made at the high-grade but shorter life Pogo mine. Reserves increased 21% with a 7% increase to grades, which helps build medium-term confidence at the site.”