Polymetals Confirms High-Grade Silver-Zinc Remains Intact After 1996 Collapse
Polymetals confirms high-grade silver-lead-zinc mineralisation in Upper Main Lode at Endeavor Mine
Polymetals Resources has reported encouraging drilling results from the upper levels of the Main Lode at its Endeavor Mine in Cobar, New South Wales. The first 12 holes of a 34-hole campaign have confirmed broad zones of high-grade mineralisation remain intact in an area historically considered largely sterilised following a 1996 ground collapse. 11 of 12 holes intersected significant silver-lead-zinc mineralisation, with intercepts adjacent to existing underground development and infrastructure.
This is not greenfield exploration — it represents resource recovery within an established mining environment, materially reducing development risk and capital requirements if the mineralisation is converted to mining inventory.
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Drilling returns broad zones of high-grade polymetallic mineralisation
Assay results from the initial 713.6 m drilled (of approximately 3,100 m planned) have returned thick, high-grade intercepts across multiple holes. Several intervals exceed 30 metres at silver-equivalent grades above 400 g/t AgEq, demonstrating continuity of ore-grade mineralisation with widths that support potential stope-level mining.
| Hole ID | Interval (m) | AgEq (g/t) | Silver (g/t) | Zinc + Lead (%) |
|---|---|---|---|---|
| POL009 | 45.2 | 436 | 197 | 19.9 |
| POL002 | 33.0 | 439 | 209 | 18.0 |
| POL010 | 33.0 | 408 | 205 | 15.1 |
| POL007 | 24.5 | 473 | 207 | 19.0 |
| POL011 | 26.7 | 439 | 227 | 16.4 |
| POL008 | 14.9 | 494 | 304 | 14.4 |
Gold assays for these holes are awaited and will be reported separately. The silver-equivalent (AgEq) calculation excludes gold.
These intercepts demonstrate continuity of ore-grade mineralisation with widths exceeding 30 metres in several holes — scale that supports potential stope-level mining and indicates meaningful tonnage may remain in-situ.
What is silver equivalent and why does it matter for polymetallic deposits?
Silver equivalent (AgEq) is a standardised metric that converts the grades of zinc, lead and copper into a single silver-equivalent figure, allowing investors to compare intercepts across different polymetallic deposits. The calculation uses assumed metal prices (US$62/oz silver, US$3,500/t zinc, US$13,600/t copper, US$1,950/t lead) and metallurgical recoveries (80% silver, 89% zinc, 85% copper, 85% lead).
Understanding AgEq helps investors assess the economic potential of polymetallic intercepts without needing to manually calculate value across four different metals. The current AgEq figures do not include gold, as gold assays for this drilling batch are pending.
Silver is deemed the appropriate metal for equivalent calculations because it is always associated with lead, zinc and copper mineralisation in the ore material at Endeavor. All metals included in the AgEq calculation have reasonable potential to be recovered and sold.
Reinterpreted collapse zone opens upside potential
A ground failure during previous mining operations in 1996 led to an area being considered largely sterilised. Recent reinterpretation of historic mine records, survey data and underground inspection now suggests the collapse zone may be materially smaller than previously assumed, creating the opportunity to define substantial volumes of in-situ mineralisation that remain intact.
Historical interpretation assumed the collapse sterilised a significant volume of mineralisation. New analysis suggests the affected zone is smaller than legacy assumptions indicated. The ongoing drilling programme is designed to define the continuity and boundaries of intact mineralisation.
If the collapse zone is confirmed to be smaller than previously interpreted, Polymetals may be able to add tonnage to Endeavor’s mining inventory from an area that was effectively written off.
Proximity to existing infrastructure enhances development pathway
The mineralisation sits adjacent to existing underground development and immediately next to the high-grade Upper North Lode. This reduces the capital and time required to bring any new resource into production, compressing the timeline from resource definition to potential production.
Infrastructure proximity materially de-risks the conversion of exploration tonnes into mining inventory, as the area benefits from established infrastructure already in place at Endeavor.
Executive Director outlines strategic rationale
Jess Oram, Executive Director
“Our reassessment of historical mine records and new drilling suggest the extent of the 1996 stope collapse may have been considerably smaller than previously interpreted.
“The results from the first 12 holes provide strong support for that view. Every hole (bar one) has intersected significant mineralisation demonstrating that substantial volumes of high-grade silver-lead-zinc remain intact adjacent to the collapse boundaries.”
Jess Oram, Executive Director
“What makes these results particularly important is their location. The mineralisation occurs within an established mining environment, close to existing infrastructure and immediately adjacent to the high-grade Upper North Lode.”
Next steps and drilling programme outlook
The 34-hole campaign targeting approximately 3,100 m remains underway. Results from the first 12 holes have provided sufficient encouragement to continue the programme.
- 34 total holes planned for approximately 3,100 m
- 12 holes completed (713.6 m) — results reported in this announcement
- 22 holes remaining
- Programme designed to improve geological confidence, assess continuity, and support evaluation of potential mining opportunities
Continued drilling success could support a resource update and potential inclusion of this area in Endeavor’s mine plan. Investors should watch for further assay releases as the programme progresses, particularly given that gold assays for the initial holes are awaited and will be reported separately.
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Investment thesis — why this matters for Polymetals shareholders
- Resource recovery potential — Drilling is targeting mineralisation within an established mine, not a new discovery requiring greenfield development
- High-grade intercepts — Results include intervals exceeding 30 metres at silver-equivalent grades above 400 g/t
- Infrastructure advantage — Proximity to existing underground development and the Upper North Lode reduces capital and timeline risk
- Upside from reinterpretation — If the collapse zone is confirmed smaller than assumed, meaningful tonnage could be added to mining inventory
- Catalysts ahead — Remaining 22 holes and pending gold assays provide near-term newsflow
Results from the ongoing drilling campaign will determine whether this area can contribute to Endeavor’s future production profile. The combination of high-grade results, established infrastructure, and potential upside from a reinterpreted collapse zone positions this programme as a meaningful catalyst for Polymetals.
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