ASX-listed rutile and graphite developer Sovereign Metals has started a 12 000 m drilling programme to establish a prefeasibility study (PFS) across the Kasiya rutile project, in Malawi.

Drilling will be on a 200 m by 200 m grid to target indicated classification, which should convert to probable reserves as part of the forthcoming PFS.

The company is also starting a core (push-tube) drilling programme across inferred areas of the mineral resource estimate, targeting nearer-surface, high-grade areas for conversion to indicated and measured resources.

In parallel to these mechanical drill programmes, Sovereign is continuing extensional and regional hand-auger drilling with multiple drill teams active across its extensive target areas at Kasiya with the aim to expand the overall mineralised footprint and identify further high-grade rutile zones.

The low-cost and low-impact hand-auger drilling technique has proven to be an effective exploration tool in the initial delineation of the Kasiya rutile and graphite mineral resource estimate (MRE).

In April, the company updated Kasiya’s MRE of 1.8-billion tonnes at a grade of 1.01% rutile, confirming the project as a tier-one deposit and a potential major source of low carbon dioxide footprint critical raw materials natural rutile and natural graphite.

The updated MRE positions Kasiya as the largest rutile deposit in the world, with more than double the contained rutile of its nearest rutile peer Sierra Rutile.

In addition, the graphite by-product MRE at Kasiya confirms it as one of the largest flake graphite deposits in the world.

The MRE has broad zones of high-grade rutile occurring contiguously across a large area of over 180 km², with rutile mineralisation lying in laterally extensive, near-surface, flat “blanket” style bodies in areas where the weathering profile is preserved and not significantly eroded.

The deposit is expansive with high-grade rutile mineralisation commonly grading 1.2% to 2% in the top 3 m to 5 m from surface, while moderate grade mineralisation, generally grading at between 0.5% to 1.2% rutile commonly, extends from a depth of 5 m to end of hole where it remains open at depths of more than 10 m.

Based on the updated MRE, a number of areas remain open at depth and mineralisation is expected beyond the limit of previous drilling with many holes showing +1% rutile at bottom of hole.

Meanwhile, Sovereign is nearing completion of the updated scoping study, which will build on the initial scoping study released in December 2021.

The updated study will incorporate the significant increase in the MRE tonnage as announced in April, assessing higher-grade throughput, increased production rates and a longer mine life.