Perth-based Zenith Minerals (ASX: ZNC) says a program of “elevated activity” is underway at its wholly-owned Australian core assets with a view to defining a commercial-sized precious and base metals inventory.
The program will be a follow-up to exploration completed over the past 12 months at the Split Rocks and Red Mountain gold projects (in WA and Queensland respectively) as well as the Develin Creek copper-zinc project, also in Queensland.
It will include more than 1,500m of diamond drilling, 5,000m of reverse circulation drilling, 6,000m of aircore drilling and the collection of over 5,000 soil samples.
Most of the work is anticipated to occur in the first half of the year and will include an initial investigation of surrounding feeder projects.
Zenith executive chairman Peter Bird said the company remains focused on unlocking the value of its “extensive” precious and base metals portfolio.
“Our work will be heavily-weighted towards our three more advanced core projects where we believe the probability of material commercial success is the greatest, [as well as] a suite of feeder projects which provide very good follow-on opportunities,” he said.
“Our overall portfolio will continue to be refined to deliver on our strategy, with non-core assets to be divested and new opportunities being added.”
Ongoing exploration at Red Mountain is following-up on high-grade, near surface gold and silver intersected in a maiden program last June which provided highly-encouraging, high-grade results.
Drilling has so far outlined a discrete sub-vertical high-grade gold zone (known as the Western Zone) to a vertical depth of 180m.
Two holes have returned individual assays peaking at 34.2 grams per tonne gold and 10.4g/t gold, with reports that the mineralisation is associated with a stockwork of base metal stringer veins in altered diorite, granodiorite and granite.
Five separate occurrences of visible gold have been confirmed by assays, and will see Zenith increase the next phase of drilling to below the 180m mark.
Ground-based induced polarisation and airborne magnetic geophysical surveys over the immediate area of interest will be carried out in March to assist with target refinement while soil sampling will aim to define possible extensions to known mineralisation.
In 2020, Split Rocks yielded high-grade, near-surface mineralisation across multiple targets including Dulcie North, Dulcie Laterite Pit, Estrela and Dulcie Far North.
The most advanced of these is the Dulcie Laterite Pit where Zenith completed a total 27 reverse circulation holes for 3,026m during the December quarter.
Gold zones at this prospect appear to be locally stacked, open to the east and down-dip to the west, and have been earmarked for a second phase of drilling comprising an initial 21 holes.
Flora surveys completed in the latter part of 2020 will allow for follow-up drilling of the Dulcie North and Far North targets comprising several reverse circulation holes and an initial aircore drilling program of 60 holes.
In December, Zenith reported results from a seven-hole maiden drill program at the greenfields Snook copper prospect over 200m of strike.
First pass assays included 3m of massive and semi-massive sulphides at 20m depth in the northern-most drill hole grading 1.6% copper, 1.1% zinc, 43g/t silver and 0.2g/t gold.
Mr Bird said the Develin Creek project was a high-order VMS-style (volcanogenic massive sulphide) copper-base metals target spanning more than 50km strike length of favourable stratigraphy.
“VMS systems tend to occur in discrete commercial clusters and this project appears to be presenting such an opportunity,” he said.
“We plan to systematically advance [Develin Creek] throughout 2021 to build upon its JORC resource.”
In 2015, Zenith released an inferred mineral resource for the project of 2.57Mt at 1.76% copper, 2.01% zinc, 0.24g/t gold and 9.6g/t silver (2.62% copper equivalent).