At Gorno, diamond drilling at Pian Bracca was focused on extending Pian Bracca mineralisation towards the Zorzone mineral resource, now at a total drilled strike length of around 630 metres.
Results have confirmed that the high-grade and thickness of mineralisation in the Pian Bracca corridor is consistent and controlled by several east-west faults.
Within the corridor results returned some of the highest grades and thickest mineralisation yet drilled at Gorno, with drill hole PBD19 returning:
- 8 metres at 5.8% zinc and 1.9% lead (7.7% zinc-lead) and 34 g/t silver from 35.5 metres, including 4 metres at 10.5% zinc and 3.3% lead (13.9% zinc-lead) and 61 g/t silver from 35.5 metres.
New exploration corridor
Recent exploration has also defined a structural control which opens into a new southern Pian Bracca exploration corridor.
Initial drilling and mapping indicates a repeating zone of the same highly mineralised strata seen in the rest of Pian Bracca.
Drill hole PBD27 intersected four mineralised intervals totalling 17.9 metres, including the following standout grades:
- 5.9 metres at 9.7% zinc and 3.0% lead (12.7% zinc-lead) and 54 g/t silver from 79 metres;
- 2.3 metres at 9.3% zinc and 1.7% lead (11.1% zinc-lead) and 10 g/t silver from 94.9 metres including 0.7 metre at 29.8% zinc and 4.8% lead (34.6% zinc+lead) and 28 g/t silver from 95.6 metres; and
- 7.1 metres at 7.9% zinc and 2.7% lead (10.6% zinc-lead) and 8 g/t silver from 107.9 metres.
Plan view of the reported drilling showing the priority target areas and pad locations for upcoming drilling and how the drilling footprint is being expanded.
Extended Gorno footprint
During the quarter, Alta announced the results of sampling from new mineralised areas that significantly expand the current exploration footprint of the greater Gorno Project area to now include the Fontanone mineralised horizon.
This extends the strike length 2.5 kilometres and 750 metres down-dip from Pian Bracca.
These extensional zones will form part of the exploration focus in the drill program for 2021
Additionally, a further horizon of high-grade zinc sulphide mineralisation has also been identified at Arera, where zinc oxide mineralisation was historically mined about 1.5 kilometres east of Pian Bracca.
The company is confident that this demonstrates the widespread potential to discover new areas of primary sulphide mineralisation alongside historical oxide mining areas.
Exploration licence renewed
A new consolidated Gorno exploration licence (EL) was awarded to July 5, 2023, with the right to extend for a further three years to 2026.
The EL grants the company the right to explore for lead, zinc, copper, silver and all associated metals, and covers around 1,200 hectares centred over the Gorno mine encompassing the historical underground workings and areas of near-mine prospectivity.
The grant of the EL authorises both the work program for the drilling and associated underground works required for Alta’s exploration program and allows the company to continue to explore prospective ground whilst the application that was lodged in December 2019 for the mining licence (ML) renewal is being assessed by the various stakeholders.
Plan map of Punta Corna exploration areas showing cobalt/nickel vein locations.
Punta Corna campaign begins
During the quarter a field campaign at Punta Corna Project commenced to explore for extensions to the known veins and to discover additional mineralised veins containing cobalt, nickel, copper and silver, which were historically mined at the project.
This work will help the company develop a more advanced understanding of the geology and genesis of the deposit, to potentially discover additional mineralised veins and to plan and execute a diamond drilling program to determine the extent and tenor of the mineralisation that remains in-situ at Punta Corna.
The company considers Punta Corna both a geologically and commercially exciting organic growth project with potential to be allied with the future macro prospects for global cobalt demand and the development of an extensive battery manufacturing industry domestically in Europe.
Well-funded going forwards
On July 10, 2020, Alta announced a share purchase plan (SPP) whereby shareholders were provided the opportunity to subscribe for shares at 0.4 cents per share with one free attaching option for every three new shares.
In response to the strong demand from shareholders, the company increased the size of the SPP by $1.5 million above its original target of $0.5 million, raising a total of $2 million.
The proceeds, together with the $3.6 million share placement to institutional investors, provided a total of $5.6 million ensuring that Alta is well funded to continue the ongoing exploration drilling activities at the Gorno Project.