Whilst ASX listed and Africa focussed Sovereign Metals has been busy proving up its high quality Malingunde graphite flake deposit in central Malawi, a recent program of re-assaying historical drill holes in the same area has unearthed high-grades of the titanium mineral rutile.
Significantly, nearly 80% of the 125 re-sampled shallow hand-auger drill holes around the flagship Malingunde project and the Lifidzi area, 40km to the southeast, contained significant rutile mineralisation, with an average weighted grade of 1.89% titanium dioxide.
At Malingunde, results from the near surface vertical holes returned grades up to 9 metres grading 3.29% titanium dioxide and 10m @ 3.02% titanium dioxide.
The new assay results from Malingunde exceeded the company’s expectations and were much higher than a suite of metallurgical samples obtained from the same project in 2018.
The company has identified a 10.5 square kilometre zone of near-surface mineralisation at Malingunde, which gives some idea of the potential scope of this opportunity.
Similarly, the Lifidzi area produced promising drill intersections that included 10m @ 2.94% titanium dioxide and 7m @ 2.62% titanium dioxide.
The beauty of the ore is its occurrence in shallow, soft, “free digging” saprolite rock, where the sought after titania mineralisation presents as discrete, clean liberated grains.
According to Sovereign management, this potentially makes the ore bodies amenable to concentration by inexpensive, conventional mineral sands processing techniques.
The company added that a detailed program of mineralogical and metallurgical test work will now be required to ascertain the mineralogy of samples and optimise a flowsheet to increase overall rutile recoveries and hence, ore concentrate grades.
An initial sighter mineralogy and metallurgical program conducted last year on lower-grade samples, showed that grades of 0.86% titanium dioxide were recovered to an ore concentrate at a recovery of 58%.
Sovereign said at the time that market specification rutile-(leucoxene) concentrates with titania contents ranging from 78% to 90% could be easily produced by simple extractive methods.
The high grade results have encouraged Sovereign to conduct a larger, regional assessment of rutile potential across its extensive ground holdings in Malawi, that cover nearly 4,000 square kilometres.
Company Managing Director Julian Stephens said: “Sovereign is focused on developing the world-class, low-cost flake graphite operation at Malingunde with the 50t pilot plant work set to commence shortly as we ramp-up DFS activities.”
“This discovery of large areas of high-grade TiO2 suggests the potential also for significant rutile deposits within Sovereign’s large ground holding (in Malawi).”
“Given the currently strong fundamentals of the titanium feedstock market, the company intends to undertake further exploration and metallurgical studies to advance this potential rutile opportunity.”
Purified titanium sheet or “bar”, which can be generated from a chemical process that consumes titanium oxide powder – a refined form of rutile – is currently fetching nearly $57,000 per tonne and the metal has many industrial uses due to its light weight and high strength.
Sovereign has now come across another valuable mineral commodity during the broader exploratory evaluation of its land holdings in Malawi.
Time will tell if the titanium-rich rutile mineralisation it has uncovered plays second fiddle to the impressive flake graphite deposits for long, or whether the titanium prospects will take on an economic life of their own.
