Polymetals Resources Ltd (ASX: POL) has received the final assay results from its Upper Main Lode drilling program. The work took place at the Endeavor silver-zinc-lead mine near Cobar, New South Wales. The Company reported the results on 30 Sep 2026.
The Polymetals Endeavor Mine expansion story now shifts from drilling towards mine planning. The drilling behind this high-grade silver-zinc discovery has already fed the Endeavor Mine silver-zinc resource. For readers following the mining sector, the next steps are now the story.
Polymetals Endeavor Mine Expansion Gains a Finished Drilling Program
Polymetals began by testing its reinterpretation of the historic Upper Main Lode subsidence zone. That work defined the shape and continuity of previously unrecognised in-situ mineralisation. It then produced a new Upper Main Lode Mineral Resource.
Polymetals reported earlier results on 24 Jun, 22 Jul and 12 Aug 2026. Those results showed broad, consistent, high-grade silver-zinc-lead sulphide mineralisation around the old subsidence zone. The latest holes mainly tested the shallower oxidised and supergene zone above it.
Figure 1: Long section of the Endeavor Mine marking the Upper Main Lode target zone [Courtesy: Polymetals]
Standout Intersections in the High-Grade Silver Zinc Discovery
Polymetals named POL038 as the strongest intersection of this drilling phase. It returned 14.2 m at 494 g/t silver, 4.8% zinc and 7.1% lead. The Company also reported 0.75 g/t gold over that interval.
| Hole | Interval | Silver | Zinc | Lead | AgEq |
|---|---|---|---|---|---|
| POL038 | 14.2 m | 494 g/t | 4.8% | 7.1% | 687 g/t |
| POL031 | 36.2 m | 101 g/t | 0.03% | 3.2% | 130 g/t |
| POL036 | 13.4 m | 18 g/t | 0.09% | 8.3% | 93 g/t |
AgEq means silver equivalent and does not include gold.
Oxidised and Supergene Mineralisation
Polymetals said weathering has changed the original sulphide minerals and moved metals around. Most shallow holes therefore show very low zinc, with locally strong lead, silver and gold. POL038 stands apart because it kept substantial zinc alongside high silver and lead. That makes it the standout in this high-grade silver zinc discovery.
POL038 also hit chalcocite, a copper mineral, at 0.7 m at 9.2% copper. That interval returned 1195 g/t silver. Executive Director Jess Oram said the final results “complete a highly successful Upper Main Lode drilling program”.
Figure 2: Upper Main Lode drillholes cutting through oxidised ore above the sulphide zone [Courtesy: Polymetals]
Endeavor Mine Silver-Zinc Resource: What the Numbers Say
Polymetals reports the Upper Main Lode Mineral Resource at about 1.6 million tonnes (Mt) at 8.5% zinc, 6.0% lead and 235 g/t silver. It forms part of the updated Endeavor Mine silver-zinc resource of 20.7 Mt at 7.5% zinc, 4.2% lead and 82 g/t silver. The cut-off is 5% lead plus zinc.
| Resource | Tonnes | Zinc | Lead | Silver |
|---|---|---|---|---|
| Upper Main Lode | About 1.6 Mt | 8.5% | 6.0% | 235 g/t |
| Endeavor global in-situ | 20.7 Mt | 7.5% | 4.2% | 82 g/t |
Polymetals splits the underground resource across three JORC categories. The table below shows the Endeavor Mine silver-zinc resource under the JORC 2012 reporting standards.
| JORC category | Mt | Zinc | Lead | Silver |
|---|---|---|---|---|
| Measured | 5.9 | 7.6% | 4.6% | 82 g/t |
| Indicated | 11.1 | 7.5% | 4.3% | 86 g/t |
| Inferred | 3.7 | 7.4% | 3.1% | 70 g/t |
| Total | 20.7 | 7.5% | 4.2% | 82 g/t |
Core Recovery and Mining Context
Polymetals faced broken, friable and heavily weathered ground in the shallow zone. Core loss ranged from 1.5% to 70% across the reported intersections. Reported grades relate only to recovered core, with zero grade given to lost material.
The Company excludes this oxidised and supergene material from its Mineral Resource estimate dated 7 Sep 2026. Development needed to reach the high-grade resource will expose parts of the zone. Any high-grade material found will be assessed as potential direct shipping ore. The Company has not assumed that isolated high-grade intersections are continuous enough for resource estimation.
Industry Outlook
Polymetals describes the Cobar Basin as one of Australia’s most prospective polymetallic districts. The Endeavor Mine silver-zinc resource sits within that setting. For the Polymetals Endeavor Mine expansion, the Company plans to leverage existing infrastructure.
Polymetals Resources Ltd (ASX: POL) Share Price
- Last price: A$0.840 per share
- Market capitalisation: A$252.90 million
- 52-week range: A645 per share
Future Direction and Impact on Endeavor Mine Planning
Polymetals is progressing mine design and technical studies using the updated Upper Main Lode Mineral Resource. An Ore Reserve estimate over the entire Endeavor orebodies has commenced. The Company will publish it in Q2FY27.
Polymetals has also designed development to potential supergene mineralisation, and it will commence shortly. The Polymetals Endeavor Mine expansion will therefore be tested by mine design, Ore Reserve work and face sampling. That is where the high-grade silver-zinc discovery and the Endeavor Mine silver-zinc resource meet real mining.
Colitco will track the Ore Reserve estimate due in Q2FY27 and the results of development into the supergene zone.
FAQ
Q1. What did Polymetals announce on 30 Sep 2026?
Ans. It reported final assays from the Upper Main Lode drilling program, completing that program.
Q2. Which hole gave the best result in the high-grade silver-zinc discovery?
Ans. POL038 returned 14.2 m at 494 g/t silver, 4.8% zinc and 7.1% lead.
Q3. What comes next for the Polymetals Endeavor Mine expansion?
Ans. Mine design continues, and an Ore Reserve estimate is due in Q2FY27.
Q4. Why does the oxidised zone matter for the Endeavor Mine silver zinc resource?
Ans.Polymetals excludes it from the resource estimate, but mining development will expose it.
Disclaimer
This article is for informational purposes only. All company data is sourced from the Polymetals ASX announcement, and share price data is taken from market data supplied. Please verify all figures before making any decision. Investing carries risk, and any investment is made at the investor’s own risk. Colitco does not hold a position in the above-mentioned Company.
Luke Carlino is a seasoned Copywriter, Content Strategist, and Social Media Manager specialising in Mining, Finance, and Business journalism. With more than a decade of industry experience, he brings rigorous editorial standards and commercial acuity to every project.
