The playbook — copper · October 1, 2026
NexMetals' Selebi copper-nickel resource grows 72% — all of it low-confidence
A past-producing Botswana mine now counts 32.47 million tonnes at high grade, but every tonne sits in the lowest confidence tier.
NexMetals Mining put a new number on its Selebi deposit in Botswana, an old copper-nickel mine that used to produce. The company now counts 32.47 million tonnes of rock grading 1.53% copper and 0.98% nickel — meaning every hundred tonnes carries roughly a tonne and a half of copper and about a tonne of nickel. That is 495.4 thousand tonnes of contained copper and 316.8 thousand tonnes of contained nickel. The headline is the jump: the resource grew 72%, up from 18.89 million tonnes at 1.69% copper and 0.88% nickel in the 2024 estimate. The tonnage went up; the copper grade came down a notch while nickel ticked up.
The grade is the story worth understanding. Most big copper mines — porphyry deposits — run 0.4% to 0.6% copper. Selebi’s 1.53% is several times richer, and it carries nickel and a little cobalt on top. The ore sits in massive-sulphide veins averaging about 7 metres thick, along a structure that runs 1,500 metres near surface and widens to 2,500 metres at depth, still open below. The release says the resource was stretched a maximum of 100 metres along strike and 150 metres down plunge from known holes, with mineralization intersected at depths of up to approximately 1,950 metres below surface. The estimate was signed off by J.C. Witley of the independent MSA Group, and metallurgy and sample checks (sent to an accredited lab in Johannesburg) look clean. All of which the market has, so far, ignored: the stock fell about a fifth over three months while copper rose 7% and the copper-miner index climbed nearly 11% — a divergence that points at company-specific worries, not the sector.
Here is what tempers it. Every tonne of that 32.47 million is classified Inferred — the lowest-confidence category under the rules, and the release itself says there is not enough drilling to upgrade it. Some of the older data came from a lab run by the prior operator, one not independent and accredited only for high-grade matte, not exploration samples; the company verified it only within “reasonable limits.” Nickel recovery in the metallurgy is only 55.6%, so a chunk of that nickel may not make it to a saleable product. And this covers only Selebi Main — the Selebi North estimate is still being finished by MSA and has no date. Watch for that North number, and for the full NI 43-101 technical report on Selebi Main, which the company says it will file within 45 days.