Olympio Metals Finds Unknown Tunnel That Could Add 500m to Jacknife Silver Strike
Key Takeaways
- An unrecorded adit ~1km south-west of the Federal shaft could extend the Conjecture Shear Zone by a further ~500m beyond the 8.22Moz Ag historical foreign estimate.
- The target sits on a patented claim, so Olympio can add holes near it to the ~1,500m maiden diamond program without waiting on permits.
- Rock chip and soil assays are expected within weeks, the nearest-term catalyst for the Olympio Metals Jacknife Silver Project.
- The historical district output of over 3.2Moz of silver at 12.7oz/t is encouraging, but it is not a JORC resource, and re-drilling aims to establish one.
- The adit's depth and scale are unknown and no antimony resource is reported, so the thesis rests on drilling that has yet to deliver results.
New adit target extends Jacknife silver strike potential by ~500m
Olympio Metals has found something on the ground that historical mining records do not explain. The first fieldwork campaign at the Jacknife Silver Project in Idaho, USA, located a previously unknown adit (a horizontal mine tunnel) along the interpreted Conjecture Shear Zone.
The adit sits ~1km south-west of the historical Federal shaft at the Conjecture Mine. According to the announcement, it represents a potential further ~500m step-out from the 8.22Moz Ag Historical Foreign Resource Estimate.
Cautionary Statement
“The resource estimate is a foreign estimate and is not reported in accordance with the JORC Code (2012); a competent person has not done sufficient work to classify the foreign estimate as mineral resources or ore reserves in accordance with the JORC Code (2012); and it is uncertain that following evaluation and/or further exploration work that the foreign estimate will be able to be reported as mineral resources or ore reserves in accordance with the JORC Code (2012)…”
No mining records could be located for the adit, so its depth and scale are unknown. That limits what can be said about it today.
What matters for investors is where it sits. The target is on a patented mining claim, so it can be tested within the maiden drilling program now underway.
Sean Delaney, Managing Director
“…This new adit target indicates that the mineralised Conjecture Shear Zone may extend for at least another 500m to the southwest, greatly increasing the scale potential of the project.”
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Maiden drilling and sampling underway on patented mining claims
The maiden diamond drilling program is estimated at ~1,500m and is, per the announcement, progressing well. It targets the up-dip positions of the historical Conjecture Mine and the area between the historical underground drives, to establish vertical continuity of mineralisation.
Patented mining claims give the company flexibility to modify the program at any time, including adding drilling to test the structure close to the new adit. The announcement also notes that on patented claims there are no permitting requirements from regulating authorities for most exploration activities. In practical terms, that means plans can change quickly without waiting on approvals.
The drilling will aim to intersect the Conjecture Shear Zone and extend the mineralised strike length to ~1km.
Work currently in progress includes:
- A completed rock chip sampling program at a number of the historical mine locations, with samples submitted for assay.
- Soil sampling along selected ridges between the Conjecture and Weber shear zones, also submitted for assay.
- Assay results, expected in the coming weeks, which is the nearest-term catalyst.
- Ongoing fieldwork and historical data review across the project area.
Scout Discoveries Corp (Scout), a private US mineral exploration company, is Olympio’s in-country technical and operational partner. Olympio holds an 80% interest in Jacknife, acquired from Scout (ASX release, 20 July 2026).
Understanding historical foreign estimates and why Jacknife’s history matters
A foreign estimate is a historical resource figure prepared before modern reporting codes existed. It is not a JORC Code (2012) Mineral Resource, and the announcement says it should only be considered a guide to the existence of mineralisation at the Conjecture Mine.
Why re-drill? According to the announcement, due to the age of the historical underground sampling and the lack of samples preserved, the company intends to re-drill the target area to seek to define a JORC-compliant Mineral Resource estimate. Modern drilling is the route to a figure investors can compare with other projects.
The announcement states the project has already produced over 3.2Moz of silver at an average grade of 12.7 ounces per ton from six mines. Table 1 of the source lists the records below, with Conjecture appearing for two production periods.
| Mine and production years | Ore (t) | Silver (oz) | Avg silver grade (oz/t) |
|---|---|---|---|
| Conjecture Mine (1913-1956) | 11,488 | 81,333 | 7 |
| Conjecture Mine (1956-1964) | 90,718 | 2,000,000 | 22 |
| Hewer Mine (1916-1950) | 28,161 | 235,890 | 8 |
| Keep Cool Mine (1937-1954) | 9,657 | 35,180 | 4 |
| Rainbow Mine (1911-1916) | 104 | 8,227 | 79 |
| Silver Leaf Mine (1925) | 16 | 608 | 38 |
| Weber Mine (1901-1981) | 115,476 | 886,556 | 8 |
| Total | 255,621 | 3,247,794 | 12.7 |
The table also records small gold, copper, lead and zinc volumes, omitted here for brevity. A total grade of 12.7oz/t points to high-grade silver in the district’s past output, though these are historical records, not current resources.
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Silver Valley location and critical minerals tailwinds
Jacknife is positioned in the Silver Valley region of Idaho. Figure 3 in the announcement places the project relative to the Silver Valley Mining District, alongside nearby operations including the Galena Mine Complex, Lucky Friday Mine and Sunshine Mine.
The announcement cautions that references to nearby properties are for contextual and illustrative purposes only. It states there is no assurance that geological continuity exists between those properties and Olympio’s tenements.
The project covers 3,940 acres in total, of which 335 acres are patented mining claims. The announcement says these claims have allowed rapid advancement to drilling.
Antimony and silver are included on the United States Geological Survey’s 2025 Critical Minerals List, supported by the US Government’s US$12 billion strategic mineral stockpile initiative. The announcement describes only minor stibnite (an antimony mineral) at Jacknife, and it does not report an antimony resource.
For investors, the next steps are straightforward. Upcoming catalysts include:
- Assay results from rock chip and soil sampling, expected in the coming weeks.
- Progress of the maiden ~1,500m diamond drilling program.
- Possible modifications to the drilling program to test near the new adit.
- Additional rock chip and soil sampling once results are received.
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