"We've made a brand new discovery in Australia's richest nickel belt," Mincor managing director David Southam said last week.

"What it shows is mature areas that don't have greenfields exploration can unearth particularly exciting deposits."

Southam estimates less than $20 million has been spent on exploration in the area over that time.

"So we've come along, we've made a discovery on a new belt called Cassini and we've progressively grown that resource," he said.

Cassini is the most advanced of the nine projects in the Explorer of the Year category of the 2020 MNN Awards, but has also been around longer than most of the others.

It was originally discovered by Mincor in 2015 as part of a regional exploration initiative led by the company's general manager of exploration Rob Hartley.

Former Mincor MD David Moore described the discovery at the time as reflective of "genius" level exploration thinking.

Cassini sits on a newly identified contact and was a blind discovery that was made as a result of systematic exploration utilising a range of techniques including regional mapping, soil sampling, aircore drilling and ground electromagnetic surveys.

However, around the time of the discovery, the nickel price had slumped to below US$10,000 per tonne, forcing Mincor to suspend mining operations.

Mincor turned its attention to gold for a couple of years, but resumed work at Cassini in early 2018.

A maiden resource of 550,000 tonnes at 3.4% nickel for 18,700t of contained nickel was reported in August 2018.

It made Cassini one of the highest grade nickel deposits in the region.

Southam, MNN's 2019 Emerging Leader of the Year, joined the company in February 2019 from Western Areas and firmly focused the company back on nickel.

Cassini became the centrepiece of Mincor's Kambalda restart plans.

Fast-forward nearly two years and Mincor has upgraded the Cassini resource a further three times and reported a maiden reserve.

Following the most recent upgrade last month, Cassini's resource now stands at 1.5 million tonnes at 4% nickel for 58,700t of nickel.

Sprott research analyst Brock Salier recently described it as the "gift that keeps on giving", given the grade has increased with every resource update.

Mincor also recently reported a maiden reserve of 34,300t of nickel at 3.3%, which is underpinning its Kambalda restart.

The total discovery cost is around 5c per pound of nickel.

Cassini has returned intersections such as 7.3m at 6.4% nickel, 15.4m at 4.7% nickel and 12.3m at 5.7% nickel.

"They're some of the best intercepts you'll ever see for nickel," Southam said.

"Particularly our last one, which was 17.6m at 5% nickel.

"To put that in context, in copper terms, you're talking about a copper intersection which is well north of 10%, so that's pretty special if you're a geologist."

Southam said Cassini was well-placed to continue to grow, given the deposit was still quite shallow and open at depth.

"Our downhole electromagnetic results show that this continues down-plunge and has a very strong conductor," he said.

"We're pretty confident this orebody is going to go on for many years."

Early development is underway at Cassini ahead of a final investment decision.

Southam noted that Kambalda deposits continued to grow as they were mined.

"They generally end up anywhere from two to four times greater than their starting position as a nickel resource," he said.

"In fact, the best one, Otter Juan, which was owned by Mincor for a period of time, started as a 17,000t nickel resource, but by the time it was finished mining, it was 317,000t of nickel.

"We haven't started mining yet so you can make your own judgement as to where this will potentially end in the future."

Cassini North is already showing signs of being another discovery.

The five holes drilled to date have all hit sulphides, 400m from Cassini Main, with a best result of 7.7m at 1.5% nickel, including 0.5m at 7.5% nickel.

"If we find more resources there, this will prove we're potentially on to another nickel belt within Kambalda," Southam said.

Mincor Resources is a nominee for Explorer of the Year in the 2020 MNN Awards for the Cassini nickel discovery.