The company is one of the few potential Australian cobalt producers from sulphide-based deposits, where cobalt production is underpinned by copper and gold.
It boasts the country’s largest undeveloped copper sulphide resources at its projects near the established mining centre of Broken Hill and cobalt provides upside to project economics.
Cobalt resources in three deposits
There is a high relative proportion of cobalt in the Mutooroo sulphide deposit while cobalt makes up a valuable component of the Kalkaroo and North Portia copper deposits, along with gold.
Solid cobalt economics are based on sulphide ores, favourable logistics and low-cost open pit mining, supported by low sovereign risk owing to South Australia being a safe legal jurisdiction.
Havilah believes it is well positioned at the right time in the right commodity cycle with the right commodities, right country and right geology.
Primary cobalt source Mutooroo contains 8,400 tonnes along with 195,000 tonnes of copper and 44,600 ounces of gold with potential to add multiples to the resource down dip and along strike.
The current JORC resource at this high copper and cobalt grade massive sulphide deposit covers less than half of the known lode outcrop.
It is a shallow deposit with less than 30 metres to sulphide ore.
Mutooroo Cobalt District is under-explored and the company aims to find further resources in shear and lode structures identified by aeromagnetics and airborne EM geophysics.
Numerous prospects from the 1960s have ore-grade copper drilling intersections but these were not assayed for associated cobalt and gold.
Havilah’s initial objective at Mutooroo is to develop a conceptual 7-year open pit design to 130 metres depth with potential for expansion both along strike and at depth.
Investigating recovery options
The company is investigating cobalt recovery options from cobaltian pyrite and is focused on completing a pre-feasibility study (PFS), mine permitting and resource extension drilling.
Kalkaroo contains 1.1 million tonnes of copper, 23,200 tonnes of cobalt and 3.1 million ounces of gold with substantial resource extension upside along strike and down dip.
PFS underway at Kalkaroo
A PFS is underway for this large, long-life, strategically positioned copper-cobalt-gold project within the Curnamona Copper Belt, which has strong geological analogies to the prolific Zambian Copper Belt.
There are substantial inferred resources and the ore body is open in all directions, highlighting the potential to extend mine life.
The belt is more than 200-kilometres long, sparsely drilled and the mineralised horizon contains copper, cobalt, gold, molybdenum, lead and zinc.
Aeromagnetics clearly identifies the prospective mineralised horizon position with shallow drilling follow-up to locate economic mineralisation.
As well as Kalkaroo and North Portia, Havilah has Croziers, Eurinilla Dome and numerous other prospects along the horizon.
North Portia contains 101,000 tonnes of copper, 600 tonnes of cobalt and 259,000 ounces of gold.
It is a natural extension of the operating Portia Gold Project and is on the same mining lease.
The initial five-year mine life is targeting oxide gold and underlying supergene copper-cobalt-gold sulphides.
There is future mining upside in the underlying primary copper-cobalt-gold sulphide mineralisation.
An MOU has been signed with Portia mining partner CMC to complete PFS and permitting.
Several technologies are potentially applicable to processing Havilah’s sulphide-hosted cobalt ores - leaching, roasting and a combination of both.
Leaching is well proven on similar pyritic ores and is being tested on Mutooroo ore.
Lab tests show that roasting is also a viable process with valuable by-products of sulphuric acid and cogenerated electricity