Core Lithium Hits 92m of High-Grade Lithium at Blackbeard, Near Finniss Plant
Key Takeaways
- NMRD104 returned 92m at 1.25% Li2O, including 73m at 1.45%, the longest mineralised intersection recorded at Blackbeard and roughly 45m in true width.
- The hole sits 80m up-dip of NRC269's 63m at 1.67% Li2O, supporting Core's case for continuity of high-grade mineralisation.
- Blackbeard lies less than 20km from the Finniss plant, and success could support throughput above the 1.2Mtpa base case.
- Not every hole delivered: NMRD101 and NMRD102 returned no significant intercept, and NMRD103 and NMRD105 came in at lower grades.
- No Mineral Resource exists yet, and only the first six holes of the 12,150m program have reported, with about 67m of NMRD108 still awaiting assays.
Thick high-grade lithium intersected at Blackbeard
Diamond drilling has returned one of the thickest lithium intersections yet recorded at the prospect. Core Lithium (ASX:CXO) reported that Blackbeard lithium drilling in hole NMRD104 intersected 92m @ 1.25% Li2O from 92m (~45m true width), including 73m @ 1.45% Li2O from 110m (~35m true width).
Li2O (lithium oxide) is the standard way lithium grade is reported. NMRD104 is the longest downhole mineralised intersection recorded at Blackbeard to date, located approximately 80m up-dip of the previously reported 63m @ 1.67% Li2O in NRC269. The company says this confirms continuity of high-grade mineralisation.
Partial results from NMRD108 returned 29m @ 1.35% Li2O from 209m (~17m true width), with remaining assays pending. Blackbeard is part of the company’s 100% owned Finniss Lithium Operation, and Core Managing Director Paul Brown described the prospect as located less than 20km from the Finniss processing plant.
Paul Brown, Managing Director
“NMRD104 is an outstanding result, delivering the longest mineralised intersection recorded at Blackbeard to date…”
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Blackbeard drill results at a glance
The announcement covers assays from five completed diamond holes (NMRD101 to NMRD105) and the first batch of samples from NMRD108. Results are mixed, which is normal for early-stage drilling.
Headline holes
| Hole | From (m) | Interval (m) | Grade (Li2O %) | Note |
|---|---|---|---|---|
| NMRD104 | 92 | 92 | 1.25 | Main intersection |
| NMRD104 (incl.) | 110 | 73 | 1.45 | High-grade inclusion |
| NMRD108 | 209 | 29 | 1.35 | Partial results, remaining assays pending |
| NMRD103 | 330 | 19 | 0.59 | Lower part of deeper pegmatite |
| NMRD105 | 142 | 4 | 1.11 | Upper pegmatite |
| NMRD105 (and) | 203 | 13 | 0.72 | Lower pegmatite |
Intervals are downhole lengths, reported using a 0.3% Li2O lower cut-off with up to 3m of internal dilution.
Strike and up-dip continuity
NMRD108 was designed to test continuity along strike to the south-west. It sits approximately 50m along strike from SRC117 (41m @ 1.63% Li2O from 137m).
NMRD104’s mineralisation sits within a 100m pegmatite intersection from 91m to 192m. Its estimated true thickness of about 45m is consistent with the up to 45m true thickness previously interpreted at Blackbeard.
Holes with limited results
Not every hole delivered. NMRD101 and NMRD102 were deep holes (760.7m and 624.1m) and returned no significant intercept. NMRD101 was co-funded by the Northern Territory Government.
NMRD103 and NMRD105 returned lower-grade results. The five holes and their purpose were:
- NMRD101: test the depth extent of the pegmatite in the central area.
- NMRD102: test the depth extent of the pegmatite in the central area.
- NMRD103: test the down-dip extent of mineralisation below SRC117 and SRC118.
- NMRD104: test continuity of the high-grade zone about 80m up-dip of NRC269.
- NMRD105: drilled to the northeast of NMRD104 and previously reported hole SRC119.
What diamond drilling reveals about pegmatite systems
Diamond drilling extracts a solid core of rock, which geologists log and cut for assay. That gives a direct look at what is underground, rather than loose chips.
Because holes cut through steeply dipping rock at an angle, intersections are downhole lengths, not true thickness. The company says true width typically represents about 50-90% of the intercept width, which is why NMRD104’s 92m downhole length equates to roughly 45m true width.
Finniss mineralisation is hosted in pegmatite, a coarse-grained igneous rock. The predominant lithium-bearing mineral is spodumene, and Blackbeard is described as hosted in large, massive, sub-vertical pegmatite bodies.
Thick, continuous, high-grade intercepts are what companies look for before attempting a resource estimate. For you as an investor, that is the step between an exploration result and something that can be valued. Key reporting points:
- A 0.3% Li2O lower cut-off was used for reporting intersections.
- Composites are length-weighted averages of assayed intervals.
- No Mineral Resource has been estimated for Blackbeard, as data spacing is not yet sufficient to establish geological and grade continuity.
Blackbeard’s role in Finniss growth
Investment thesis
The company says Blackbeard has the potential to provide additional high-grade resources to support mining studies and production options. Its proximity to the Finniss processing plant, established logistics chain and existing infrastructure provide what it calls a strong platform for assessing future development options.
Together with the existing >2Mtpa crushing capacity, successful resource definition at Blackbeard may support ongoing assessment of plant throughput expansion above the current 1.2Mtpa base case (referenced to the FID announcement of 18 March 2026).
This is potential, not a guarantee. No Mineral Resource or production target exists for Blackbeard, so everything depends on further drilling.
The strategy sits alongside Carlton, already converted to Ore Reserve, and development progressing at BP33.
Paul Brown, Managing Director
“Blackbeard represents an exciting growth opportunity for Core, with the potential to become a significant future source of high-grade ore feed for our Finniss operation…”
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Next steps as drilling continues
The Blackbeard exploration program is a staged and gated diamond drilling campaign totalling 12,150m. These results cover only the first six holes.
Assays remain pending for the remaining ~67m of the 96m pegmatite intersection in NMRD108. Results are to be released progressively as they become available.
Resource Definition Drilling is also ongoing at BP33. The announcement did not disclose timelines for further results, or any resource estimate for Blackbeard.
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