Historical work has identified widespread near-surface columbo-tantalite mineralisation at Australasian Metals’ Atex project in Côte d’Ivoire, adding a potential tantalum stream to its lithium strategy. The results are encouraging, but the underlying estimate is non-JORC, unverified and based on incomplete historical records.
- Historical concentrate grades reached 14,700 g/m³ at Zone 2
- A 40-tonne historical estimate is not JORC compliant
- 2022 testwork indicated strong gravity and magnetic separation response
- Modern auger and diamond drilling contractors are being finalised
- Tantalum concentrate prices have risen sharply during 2026
Historical Tantalum Grades Add a Second Target
Australasian Metals Limited (ASX:A8G) has found a potentially valuable second dimension to its Atex lithium project, with historical sampling pointing to near-surface columbo-tantalite mineralisation across Spodumene Hill and two adjacent zones in Côte d’Ivoire. Reported concentrate grades reached 14,700 g/m³ in Zone 2, although these figures represent recovered columbo-tantalite per cubic metre of pit material rather than in-situ Ta₂O₅ grades.
The historical results came from systematic pitting carried out by Côte d’Ivoire’s SODEMI under geologist H. Adam in 1965 and 1966. Spodumene Hill returned grades of 50 to 655 g/m³, while Zone 1 produced 50 to 4,600 g/m³ and Zone 2 returned 55 to 14,700 g/m³. The company said both Zone 1 and Zone 2 were incompletely tested, leaving modern follow-up work to establish whether the mineralisation is continuous or economically meaningful.
Forty-Tonne Estimate Carries Heavy Qualifications
Adam’s work also generated a historical estimate of approximately 40 tonnes of columbotantalite across Spodumene Hill, Zone 1 and Zone 2, at broadly estimated grades of 155 to 295 g/m³. That number is not a Mineral Resource or Ore Reserve, does not comply with the JORC Code and has not been independently verified by a Competent Person.
The limitations are unusually important here. Australasian said the original 1966 laboratory sheets have not been located, while pit dimensions, sample masses, density and volume assumptions, recovery methods and the calculation behind the 40-tonne figure are not fully documented. The announcement also notes that no modern quality assurance and quality control applies. In other words, the estimate is useful as an exploration lead, not as a production target or valuation input.
Preliminary Testwork Points to Physical Separation
A 2022 programme by Firering Strategic Minerals, from which Australasian holds an exclusive option to acquire a majority interest in Atex, collected two 100-kilogram composite samples from pits around Spodumene Hill. CoreMet Mineral Processing found columbite was the only tantalum-niobium-bearing mineral phase in both samples, with more than 95% of the columbite occurring in highly liberated particles.
Both composites responded well to gravity and magnetic separation, with the shaking-table work producing an upgrade ratio of more than 120 times. That is a useful early processing signal, but not a flowsheet: the sample size was too small for definitive conclusions, and recoveries, concentrate grades, mass balance and overall process performance remain unestablished.
Drilling Must Convert History into Modern Evidence
The company is finalising auger and diamond-drilling contractors ahead of Atex’s maiden drilling programme. It intends to include tantalum in multi-element assays during the lithium programme, with dedicated tantalum bulk sampling to follow if initial results justify it. That work will need to test continuity, primary pegmatite sources and grade distribution using modern sampling, documented volumes, QAQC and metallurgical variability studies.
The timing gives the tantalum angle extra commercial interest. Australasian said concentrate prices were broadly US$80 to US$110 per pound of Ta₂O₅ during 2025 before rising substantially in 2026 amid tighter supply and stronger demand. But market strength cannot substitute for a compliant resource, and the next meaningful re-rating of the story will depend on whether drilling and bulk sampling reproduce the historical signal under contemporary standards.
Bottom Line?
Atex now has a tantalum exploration case alongside lithium, but the decisive evidence has yet to be drilled, assayed and processed under modern standards.
Questions in the middle?
- Will modern drilling confirm that the historical columbo-tantalite grades extend beyond isolated pits?
- Can the tantalum-bearing pegmatites produce commercially relevant recoveries and concentrate specifications?
- How much of Atex’s project value will ultimately depend on tantalum rather than lithium?