JOHANNESBURG (miningweekly.com) – TSX-listed Callinex Mines has adopted an aggressive new strategy to discover and develop high-grade copper- and zinc-rich volcanogenic massive sulphide (VMS) deposits.

The company has identified its Flin Flon and Pine Bay projects as the focus of future exploration based on potential to host the Flin Flon mining district’s next VMS deposit. Both projects are located within 20 km by road to Hudbay Minerals’ processing facility in Flin Flon, Manitoba, which is projected to require additional ore in the coming years.

President and CEO Max Porterfield said: “I am eager to lead the renewed exploration focus on VMS deposits within the Flin Flon mining camp. Prior to the 2011 spinout from Callinan Mines, the company has benefited from several VMS discoveries based in its project portfolio, including the Callinan and 777 mines. 

“Additionally, existing infrastructure and Manitoba’s favourable permitting environment can be leveraged to significantly reduce capital costs and lead times to production.”

He added that the strategic shift in focus “comes at a time when the zinc market faces a medium-term supply deficit and copper continues to have positive long-term fundamentals”.

Callinex chairperson Mike Muzylowski, who played a lead role in the discovery of 13 VMS mines in the Flin Flon Greenstone Belt, noted that the Flin Flon and Pine Bay projects were significantly underexplored at depth and had highly prospective targets defined by modern geophysics.

“A 2012 airborne electromagnetic survey flown over the Flin Flon project identified several anomalies along favourable geological structures known to host VMS deposits,” he explained.

The Flin Flon project hosts several highly prospective target zones including a high priority target with significant potential that overlaps claims of both Callinex and Hudbay. This recently identified, high-priority target is a 350 m X 400 m electromagnetic conductor with an offset magnetic anomaly located along a mapped fault within geology favourable for VMS mineralisation.

The existence of both electromagnetic and magnetic anomalies increases confidence for potential massive sulphide mineralisation, as many nonmassive sulphide conductors do not demonstrate magnetic responses. The target is interpreted to be of significant thickness based on responses from the electromagnetic survey; however, the target has yet to be proven by drilling and additional work is required.

Muzylowski noted that the Pine Bay project had four known historic deposits and was underexplored at depth where larger deposits are increasingly being found. Discoveries at depth in the Flin Flon Greenstone Belt included the Trout Lake, 777 and Lalor mines.

“My view coincides with Placer Dome’s previous exploration thesis that the historic deposits and an exceptionally large alteration zone are related to a larger deposit,” he added.

The Pine Bay project consists of a recently consolidated land package that hosts a large alteration zone related to three of the four historic resource estimates. It is believed that the alteration zone and deposits are part of a more extensive system that has been displaced by faulting. This hypothesis requires additional drilling; however, drilling by a previous company identified at depth a 210-m-wide alteration zone that includes 50 m of chloritic alteration, which has not been followed up on.

Nearly all VMS deposits in the Flin Flon Greenstone Belt are immediately related to a chloritic alteration zone and the extent of which typically has a correlation to the deposit size. In a 1993 assessment report filed with the Manitoba government, Placer Dome opined that one of the claim blocks had potential for a large VMS deposit at depth; limited exploration has been conducted since.