Apollo Minerals identifies gallium halo and more high-grade zinc at Kroussou in Gabon

Apollo Minerals Ltd (ASX:AON, OTC:APOMF) has uncovered extensive gallium enrichment and new high-grade zinc and lead mineralisation at surface across multiple targets at its Kroussou Zinc-Lead Project in Gabon, adding a potential critical-minerals dimension to the project.

The company says a review of new mapping, sampling and historic drill data has confirmed a gallium-enriched halo above and within the sedimentary rocks that host Kroussou’s zinc-lead system — with near-surface intercepts up to 36 parts per million (ppm) gallium. Additional field work has also located new zinc-bearing outcrops and extended priority target areas along the Doubaye and Ngongui embayments.

Kroussou prospects targeted for mapping.

Gallium is gaining strategic importance due to its role in high-performance semiconductors, LEDs and satellite communication systems. China currently produces more than 98% of global supply, largely as a byproduct of bauxite and zinc refining.

High-grade gallium enriched near surface

Apollo’s review of drilling and recent geological work revealed that gallium occurs in the same embayment structures as zinc and lead. Intercepts from shallow diamond drilling include:

• 3.5 metres at 36 ppm gallium from 0.4 metres,
• 2.5 metres at 34 ppm from 5.2 metres,
• 7.0 metres at 31 ppm from 5.4 metres,
• 13.2 metres at 30 ppm from 1.6 metres, and
• 11.5 metres at 30 ppm from 2.3 metres.

The company reports that the highest concentrations occur within saprolite and laterite zones — the top 0–15 metres of weathered profile — while gallium mineralisation is also present throughout the sedimentary rocks that host zinc-lead (Zn+Pb) mineralisation, particularly within siltstone horizons.

Only six of Kroussou’s 24 defined embayment targets have been drill-tested for gallium to date. Apollo now considers all 18 untested embayments, along with broader areas of laterite and saprolite, prospective for additional gallium zones.

If future work confirms that gallium can be economically recovered alongside zinc and lead, the company says it could become a valuable credit in development scenarios.

Surface mapping expands zinc-lead zones

Field mapping across the Doubaye and Ngongui prospects (TP7 and TP8) has confirmed 9.2 kilometres of prospective sedimentary contacts, generating new undrilled targets.

2025 Rock chips (Zn+Pb%) and updated mapping at TP7 and TP8.

Rock chip samples returned grades up to 3.4% Zn+Pb at TP7 and 3.0% Zn+Pb at TP8, with visible galena in outcrops. Mapping at TP8 extended the embayment by 700 metres — opening up fresh ground for future exploration — while work at Bouambo West (TP10) highlights potential extensions to areas that already returned drilling hits including 5.8 metres at 6.5% Zn+Pb.

Identified gallium anomalies from drilling; and previous Zn+Pb drill results (as metal accumulation of Zn+Pb% x thickness (m)) and soil anomalies.

Across the broader Kroussou trend, Apollo has now identified 135 kilometres of prospective geological contacts and 23 target areas.

'An exciting new dimension’

Managing director Neil Inwood said the dual discovery of new zinc-lead zones and widespread gallium enrichment materially enhances the project’s upside.

“The identification of extensive gallium enrichment within the host sediments and laterite profile adds an exciting new dimension to the Kroussou mineralisation,” he said. “This is a developing story, and the potential for additional gallium occurrences encompasses the whole of Kroussou, particularly in the broader regions of laterite/saprolite weathering and in the numerous embayment targets.”

Section 641,400E showing gallium enrichment alongside Zn+Pb mineralisation.

Next steps

Apollo will now:

• assess gallium’s distribution and mineralogy across the project,
• conduct metallurgical test work to evaluate possible extraction pathways, and
• prioritise new drilling at the expanded TP7 and TP8 targets.

Kroussou spans 2,363 square kilometres in western Gabon, with sealed-road access and direct links to port infrastructure. An exploration target — based on only six prospects — outlines 140 million–300 million tonnes at 2.0–3.4% Zn+Pb, underscoring district-scale potential.

With gallium now emerging as an additional critical-minerals opportunity, Apollo Minerals believes the project’s discovery runway remains wide open.

Read more: Apollo Minerals advances gold and base metal exploration in Gabon during September quarter