Highly-encouraging exploration results and a rejuvenation of its project portfolio during 2020 has set the scene for what Impact Minerals (ASX: IPT) believes could be a transformative year in 2021.
The junior explorer’s long-held strategy of acquiring large and strategic ground positions in highly-prospective parts of Australia has seen its portfolio grow during 2020 to include five wholly-owned projects with a focus on gold, silver and platinum group metals (PGM), as well as nickel and copper.
Extensive work programs at its flagship Broken Hill and Commonwealth projects have positioned the company for a busy year ahead.
Broken Hill boost
Impact’s Broken Hill nickel-copper-PGM project – located 20km east of the world-class Broken Hill silver-lead-zinc mine in New South Wales – was given a boost during 2020 on the back of record prices for PGMs, particularly palladium and rhodium.
A major 13,263m drilling program of delivered “breakthrough results” at every prospect tested, driven by Impact’s discovery of a proprietary multi-element ratio which is said to be a good predictor of PGM grade.
At the project’s Plat Central target, this ratio led to the discovery of high-grade nickel-copper-PGM mineralisation in a Kambalda-style channel at the base of the target ultramafic unit.
It is believed to be the first coherent zone of mineralisation uncovered in over 40 years of exploration in the area.
At Little Broken Hill Gabbro-Rockwell, the first-ever drill holes into the basal unit of the intrusion returned thick intercepts of strongly anomalous mineralisation over 1,500m.
The intrusion has similarities to China’s world-class Jinchuan nickel-copper-PGM mine and Impact said the results suggest the basal unit may host a vast repository of these metals.
In addition, the drill holes are at broad reconnaissance spacings which is “extremely encouraging” for the discovery of a significant deposit, particularly as the remainder of the 6.5km extent of Little Broken Hill Gabbro is untested.
At Red Hill, a recent stand out drill intercept suggests the prospect may be a feeder zone for Little Broken Hill Gabbro and a prime target for massive sulphide mineralisation at depth has since been identified.
Over at the Commonwealth copper-silver-base metals project, located in the northern part of New South Wales’ prolific Lachlan Fold Belt, Impact identified five new undrilled targets along trend from Alkane Resources’ (ASX: ALK) recent Boda-Kaiser porphyry copper-gold discovery.
Several campaigns of rock chip and soil geochemistry sampling along with an airborne magnetic and radiometric survey commissioned by Impact, highlighted host rocks and alteration assemblages at three of the prospects believed to be similar to those at the nearby Cadia-Ridgeway (owned by Newcrest Mining, ASX: NCM) and North Parkes mines.
The Apsley prospect was prioritised for a soil geochemistry survey following the discovery of extensive fresh copper sulphides at surface.
The survey defined a “near-textbook example” of metal assemblage zones expected around major alkalic porphyry copper-gold complexes over an area of about 4 square kilometres.
An extensive induced polarisation ground survey was also completed, with results indicating the presence of a number of priority drill targets.
During the year, Impact “rejuvenated and rationalised” its portfolio, starting in May when it staked Arkun in WA’s Yilgarn Terrane, about 130km east of Perth in an emerging new province for nickel-copper-PGM mineralisation, following Chalice Mining’s (ASX: CHN) Julimar discovery in March.
On the day of Impact’s Arkun announcement, Anglo American lodged applications for exploration licences covering 10,130sq km around the new project, prompting Impact to apply for an additional three licences to expand its ground position.
Impact has since added to Arkun with the November purchase of the Beau project 15km to the north, which is also surrounded by Anglo American’s tenements and covers an untested magnetic anomaly of similar dimension and magnitude to the Gonneville intrusion that hosts the mineralisation at Julimar.
A month earlier, the company purchased an 80% interest in the “cheap to drill” Doonia gold project, 75km east of Kambalda, where a 2.5km-long gold-in-soil anomaly is centred over numerous magnetic anomalies that have not been followed up at depth.
In July, Impact added the Pewt’s Hill and Hard Hill exploration permits to its Blackridge gold project in central Queensland, boosting its landholding to 150sq km or about 90% of the southern part of the larger Miclere-Blackridge field which has historically produced over 300,000 ounces of gold.
It also purchased a 20% interest in the silver-lead-zinc rights to a Broken Hill licence previously held by Silver City Minerals (ASX: SCI), moving it to full ownership of the mineral rights to its entire tenement portfolio at Broken Hill and ending a long and complex history of joint ventures on the tenement.
During the period, Impact divested some of its non-core assets including the Clermont gold project in Queensland, which was sold to private company Australasian Gold Limited for $100,000.
It also agreed to the sale of two tenements within the Lachlan Fold Belt suite to Orange Minerals Pty Ltd.
Impact’s management team said the divestments had left it with an “exceptional portfolio” of early stage and more advanced projects, supported by a 12-month plan to conduct extensive drilling of the highest priority targets.