Tertiary Minerals (LSE:TYM), the AIM-listed explorer developing the Mushima North project in Zambia, reported fresh laboratory results from Phase 4 infill drilling at Target A1's Discovery Zone on Monday.
All seven new holes intersected near-surface silver-copper-zinc mineralisation, with the majority ending while still in grade, indicating the deposit extends deeper than the company's existing exploration target.
That target currently stands at 15 to 30 million tonnes grading 40 to 60 g/t silver equivalent, a tabular body some 500 metres long, 300 metres wide and up to 75 metres thick.
Standout intersections included 82 metres at 53 g/t silver equivalent from just 7 metres downhole in hole 26TMNRC-057, and a higher-grade zone of 22 metres at 105 g/t silver equivalent from 64 metres in hole 26TMNRC-054, which also ended in mineralisation.
Richard Belcher, Tertiary's managing director, said the results "push the known depth of mineralisation beyond the envelope of the previously defined Exploration Target", adding that the full depth extent and any transition from oxide to sulphide mineralisation remain untested.
Results for 12 of the 39 holes drilled in the 3,639-metre Phase 4 programme have now been released.
Target A1 sits 28km east of the Kalengwa copper-silver mine, currently under redevelopment, within Zambia's Iron-Oxide-Copper-Gold belt.
Further certified laboratory results are expected over the coming weeks.
News Intelligence what this means for the company
Tertiary Minerals' Phase 4 drilling at Mushima North has extended silver-copper mineralisation beyond the depth limits of its existing 15–30 million tonne exploration target, with all seven new holes intersecting grade and several ending while still mineralised—indicating further depth potential remains untested. This validates the deposit's scale and signals a pathway to resource expansion, though only 12 of 39 Phase 4 holes have reported results so far.
The results support the case for converting the Mushima North target into a JORC resource, but the company's cash position was £78,000 as of June 2026, making near-term funding critical to complete Phase 4 drilling and advance toward a resource estimate.
Insights assembled by AI. Editor-reviewed and grounded in tickstock’s coverage and proprietary knowledge graph.
Content is for informational purposes only, not financial advice.
